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MANHATTAN

Guide 6

Critical Reasoning

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Demystifies Logical Analysis of Complex Arguments
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TABLE Of CONTENTS

1 . Argument Structure 1 1

Problem Set 23

2. Methodology 29

Problem Set 45

3. Structure-Based Family 51

Problem Set 67

4. Assumptions 91

Problem Set 117

5. Strengthen and Weaken 1 41

Problem Set 161

6. Evidence Family 1 89

Problem Set 207

7. Complete the Argument 225

Problem Set 233

8. Wrong Answer Analysis 247

Problem Set 257

Appendix A: Official Guide Problem Sets 269

Chapter/1

Critical Reasoning

Argument Structure

The Core

Building Blocks of an Argument
Argument Structure
Intermediate Conclusions and the Therefore Test

Argument Structure

Here is an example of a typical GMAT argument.

SI: Background

The expansion of the runways at the Bay City Airport will allow
S2: 1 for larger planes to travel to and from Bay City. These new
Counterpoint |\p|anes will create a large amount of noise, a nuisance for

residents who live near the airport. However, many of the X $3: Premise
residents in this neighborhood work in construction, and the ' '
contract to expand the runways has been awarded to a local
construction company. Thus, the expansion of the runways will
lead to an increased quality of life for the residents of this
neighborhood.

S4: Conclusion

There are two broad things we need to study in order to answer Critical Reasoning questions effectively
and efficiently. We need to understand the specific information given for that question, and we also
need to know how to conduct the necessary reasoning to answer a question of that type.

Lets begin first by understanding what we are given. What are the pieces of an argument, how do they
fit together, and how do we categorize them properly? In later chapters, we'll talk about what we need to
do with that information.

On the GMAT:

(1) All arguments contain at least one premise. A premise is information used by the author to support
some claim or conclusion. That information may be a fact or an opinion. In the above example, sen-
tence 3 is a premise because it helps to support the author s conclusion.

ter 1

Argument Structure

|1 (2) Most (though not all) arguments contain a conclusion, the primary claim the author is trying to

y |

prove. In the above example, sentence 4 is a conclusion.

(3) Many arguments (though not all) contain background information, which provides context to al-
low us to understand the basic situation. In the above example, sentence 1 provides background.

(4) Some arguments contain a counterpoint or counterpremise — a piece of information that goes
against the author s conclusion. In the above example, sentence 2 represents a counterpoint because it
goes against the authors conclusion.

Collectively, these categories represent the building blocks of an argument. How do we know which
sentences fall into which categories? Try to articulate your own thought process for the above argument,
then take a look at this example "decision process" of a fictional student:

Argument

Reader's Thoughts

The expansion of the runways at the Bay City
Airport will allow for larger planes to travel to
and from Bay City.

Hmm. This is a fact. It could be premise or it
could just be background. I'm not sure yet.

These new planes will create a large amount of
noise, a nuisance for residents who live near the
airport.

Now we're moving into claim territory. Something
negative will come from this project. Why are they
telling me this? I cant figure that out until I know
the conclusion.

However, many of the residents in this neighbor-
hood work in construction, and the contract to
expand the runways has been awarded to a local
construction company.

The word "however" indicates a contrast between
sentences two and three. What's the contrast?
The noise is a negative consequence of the expan-
sion, while winning a work contract is a positive
consequence. Looks like I've got a premise and a
counterpoint in these two sentences, but I don't
know which one is which yet.

Thus, the expansion of the runways will lead to
an increased quality of life for the residents of
this neighborhood.

The word "thus" usually indicates a conclusion.
And, yes, this does seem like a conclusion — this
project will have a certain outcome (better quality
of life in this neighborhood), and I can now see how
the previous two sentences fit into this conclusion.
Sentence 3 is a premise because it tells me one way
in which the quality of life might be better for these
people (they might make more money), and sentence
2 is a counterpremise because it tells me a nega-
tive consequence.

MANHATTAN
GMAT

Argument Structure

Notice how many times the reader thought Tm not sure yet" (or something along those lines). That
will happen frequently while reading an argument. Were gathering information and trying to under-
stand what each piece might be, but we won't really know how everything fits together until we know
what the conclusion is — and that might not be until the end.

The Core

The premise (or premises) and conclusion represent the core of the argument. Remember that not all
arguments will have a conclusion, but all will have at least one premise, so we will always have at least a
partial core. The core represents what the author is trying to tell me or prove to me.

Its important for us to be able to identify what specific information in an argument falls into which
category, because that helps us to take our next step: conducting the necessary reasoning in order to
answer the question. It turns out that different question types require us to perform different kinds
of reasoning; we'll discuss this in much more detail in subsequent chapters. Let s take one step now,
though, just to whet our appetites: how do the premises support the conclusion? In other words, how
does the "core" actually function in this particular argument?

In this problem, our core consists of these two pieces:

However, many of the residents

in this neighborhood work in . Thus, the expansion of the

construction, and the contract I runways will lead to an increased

to expand the runways has been ■ quality of life for the residents of

awarded to a local construction this neighborhood,

company.

The conclusion, on the right, claims that the runway expansion project will have a good outcome (bet-
ter quality of life for certain people). The premise, on the left, provides one piece of information to sup-
port this claim: the people in question may make money as a result of this project.

The premise provides one piece of evidence toward a positive outcome, but the argument is not air-
tight. For example, do we know for sure that the residents of the neighborhood are the ones who work
for the local construction company that won the contract? We don't. As we'll see, that kind of thinking
will help us when we get to the question-answering stage. For now, remember this: when we have both
a premise and a conclusion, it's critically important to understand how the premise supports the conclu-
sion.

Chapter 1

Argument Structure

Building Blocks of an Argument

Lets fully define all of the building blocks we've discussed so far.

Premise

• Part of the core of the argument; present in every argument

• Supports the authors conclusion

• Can be a fact or an opinion; can be a description, historical information, statistical or
numerical data, or a comparison of things

• Often signaled by words or phrases such as because of, since, due to, and as a result of

Conclusion

• Part of the core of an argument; present in most arguments

• Represents the authors main opinion or claim; can be in the form of a prediction, a judg-
ment of quality or merit, or a statement of causality

• Is supported by at least one premise

• Often signaled by words such as therefore, thus, so, and consequently (though note that
harder arguments might use such a word elsewhere in the argument in an attempt to
confuse us)

Background

• Not part of the core; often present, but not always

• Provides context to help understand the core

• Almost always fact-based; can be in almost any form: historical information, numerical or
other data, descriptions of plans or ideas, definitions of words or concepts, and so on

Counterpoint

• Not part of the core; only present occasionally

• Opposes or goes against the authors conclusion in some way

• Introduces multiple opportunities for traps: believing that the conclusion is the opposite
of what it is, mistakenly labeling a counterpoint the premise (and vice versa), and so on

• Often signaled by transition words such as however, yet, and but', typically, the transition
word will be found somewhere between the counterpremise and the conclusion (though
the two sentences may not be right next to each other)

MANHATTAN
GMAT

Argument Structure

Chapter 1

Argument Structure

The argument above used all four of our 1

Background - Counterpoint - Premise - Conclusion

We call that the structure because it shows the building blocks used and the order in which each ap-
peared. The simplest possible argument will contain only premises; its structure might look like this:

Premise - Premise

The GMAT can vary the type of building blocks used in a particular argument, and it can also vary
the order of those building blocks. If we can label the building blocks given in any particular argument,
that helps us to understand the purpose of each step in the chain of information, and we'll be one good
step closer to answering the question correctly.

Lets try some sample arguments. You have two tasks. First, read the argument and try to identify the
role of each sentence or major piece of information (note that one sentence could contain two different
pieces of information). Use that information to write out the structure as we just did above. Second, try
to articulate in your own words how the premises support the conclusion.

1. Budget Fitness will grow its membership base by 10% in the next six
months. Budget Fitness has recently crafted a clever ad campaign that it
plans to air on several local radio stations.

2. Last year, the Hudson Family Farm was not profitable. However, the farm will
be profitable this year. The farm operators have planted cotton, rather than
corn, in several fields. Because cotton prices are expected to rise dramati-
cally this year, the farm can expect larger revenues from cotton sales than it
previously earned from corn.

Answers can be found on page 2L

Intermediate Conclusions and the Therefore Test

We have one more building block to introduce in this chapter. Try the below problem.

The owner of a small publishing company plans to lease a new office space that
has floor-to-ceiling windows and no internal walls, arguing that the new space
will enhance worker productivity. The owner cites a recent study showing that
workers exposed to natural light throughout the day tended to report, on aver-
age, a higher level of job satisfaction than did those who worked in office spaces

building blocks; its "structure" looks like this:

MANHATTAN
GMAT

Argument Structure

that used fluorescent lighting. Thus, the owner concluded, exposure to natural
light has a positive effect on workers' job satisfaction.

The owner of a small publishing company plans
to lease a new office space that has floor-to-ceil-
ing windows and no internal walls,

This is likely to be background information because
it introduces a "plan" to do something. The argument
is probably about the plan, or a result of the plan.

arguing that the new space will enhance worker
productivity.

This might be the conclusion because it describes the
predicted future benefit of the company's plan.

The owner cites a recent study showing that
workers exposed to natural light throughout the
day tended to report, on average, a higher level
of job satisfaction than did those who worked in
office spaces that used fluorescent lighting.

And this seems to be a premise in support of that
conclusion. The workers will be more productive be-
cause the new space will provide exposure to natural
light through the floor-to-ceiling windows.

Thus, the owner concluded, exposure to natural
light has a positive effect on workers' job satisfac-
tion.

Hmm, this is strange. This appears to be the conclu-
sion as well. It uses the word "thus, " it represents an
explanation for the study's results, and it even says
that "the owner concluded" this!

This is a tough one! In this case, we have two claims that look like the conclusion. Now what?

This brings us to another building block, the intermediate conclusion (also known as the secondary
conclusion). What is an intermediate conclusion? Look at this simpler example:

The burglar is clumsy and often makes a lot of noise while robbing homes. As a
result, he is more likely to get caught. Thus, in the near future, he will probably
end up in jail.

The first sentence is a basic premise: it tells us some factual information about the robber. The second
sentence is a claim made based upon that premise: because he makes noise, he is more likely to get
caught. This is a conclusion. . . but, wait, there's a third sentence! That third sentence also contains a
claim, and this claim follows from the previous claim: because he is more likely to get caught, there is a
good chance he will end up in jail.

Essentially, a premise supports a conclusion, and that conclusion then supports a further conclusion.
The first conclusion is called the intermediate conclusion (also known as the secondary conclusion).
The second conclusion can be called the final conclusion to distinguish it from the intermediate conclu-
sion.

In the example above, the three pieces were given in this order: Premise - Intermediate Conclusion
- Final Conclusion. Arguments won't always do this, however; they might mix up the order and have
additional information thrown in. When an argument contains more than one conclusion and we're not
sure how to classify each, we can use the Therefore Test.

MANHATTAN
GMAT

Argument Structure

Chapter 1

We have two conclusions; let's call them A (he's more likely to get caught) and B (he will probably end
up in jail). All we need to do is plug the two conclusions into two sentences and ask which one is true:

Is it the case that A (he's more likely to get caught) is true, THEREFORE B (he will
probably end up in jail) is true?

Or is it the case that B (he will probably end up in jail) is true, THEREFORE A (he's
more likely to get caught) is true?

What do you think? Right, the first scenario makes sense, but the second one doesn't. That tells us that
B (he will probably end up in jail) is the final conclusion and A (he's more likely to get caught) is the
intermediate conclusion.

Let's return to the job satisfaction argument. We have two possible conclusions:

04) . . .arguing that the new space will enhance worker productivity.

(B) Thus, the owner concluded, exposure to natural light has a positive effect on work-
ers' job satisfaction.

Which scenario makes more sense?

The new space will enhance worker productivity, THEREFORE exposure to natural
light has a positive effect on workers' job satisfaction.

Exposure to natural light has a positive effect on workers' job satisfaction, THERE-
FORE the new space will enhance worker productivity.

The second scenario seems to make sense. That means that (B) is the intermediate conclusion and (A) is
the final conclusion.

As is typical of arguments with an intermediate conclusion, the premise supports the intermediate con-
clusion, which then supports the final conclusion. The premise (the second sentence) says that a study
found a correlation between natural lighting and job satisfaction. The third sentence in that argument
then makes a claim based on the study's results: the owner (not the study) concludes that exposure to
natural light actually causes better job satisfaction.

The owner claims that the new space will enhance productivity at her company because, first, a study
showed a correlation between natural light and job satisfaction, and that study then led the owner to
conclude that natural light results in better job satisfaction. So the first half of the first sentence is back-
ground, and the second half is the final conclusion.

The structure is Background - Conclusion - Premise - Intermediate Conclusion.

MANHATTAN
GMAT

Chapter 1

Argument Structure

Takeaways

A premise is a piece of evidence (fact or claim) that supports the authors conclusion.

A (final) conclusion is the authors main claim.

An intermediate conclusion is both a conclusion and a premise; it supports the final conclusion.

Background information helps to set the context for an argument.

A counterpoint or counterpremise goes against the authors conclusion.

We can use these building blocks to understand the structure of an argument. Understanding the struc-
ture will help us to answer the question.

When we have more than one conclusion, we can use the Therefore Test to find the final conclusion.
Either "A is true, THEREFORE B is true" or "B is true, THEREFORE A is true."

MANHATTAN
GMAT

Argument Structure

Chapter 1

Answer Key

Budget Fitness will grow its membership base by
10% in the next six months.

Budget Fitness has recently crafted a clever ad
campaign that it plans to air on several local
radio stations.

This is a prediction about the future, so it is a
claim, not a fact. This is a good candidate to be the
conclusion.

Budget Fitness already crafted the campaign — this
is a fact. It is also a fact that the company currently
"plans" to air the campaign (though whether it
will actually air is uncertain, since that is a future
event). This information supports the claim in the
first sentence, so it is a premise.

(Task 1) The structure is Conclusion - Premise. (Task 2) The author claims that the gym will increase
its membership in the future because the company will implement a strategy (ad campaign) that may
help attract new customers.

Last year, the Hudson Family Farm was not
profitable.

However, the farm will be profitable this year.

The farm operators have planted cotton, rather
than corn, in several fields.

Because cotton prices are expected to rise dra-
matically this year, the farm can expect larger
revenues from cotton sales than it previously
earned from corn.

This is a fact; it already occurred in the past. This
may be background info, though it may also be a
premise or counterpoint.

The word "however" indicates a change in di-
rection. This prediction is the opposite of what
happened last year. This future prediction is a good
candidate to be the conclusion, in which case the
previous sentence would be a counterpoint.

Hmm, why do we care which crop the farm is
planting?

Okay, now we can see that planting cotton will
lead to more revenue than last year. The author is
using this information to support his conclusion.

(Task 1) The structure is Counterpoint - Conclusion - Premise - Premise. (Task 2) The argument
predicts that an unprofitable farm will become profitable because a change in crops will result in higher

revenues.

Did you spot any flaws in the authors reasoning? There are several, but the biggest one is the fact that
revenues and profits are not the same thing! A company can have lots of revenue and zero profit — or
even lose money.

■T:'X\

MANHATTAN 21
GMAT *

Argument Structure

Chapter 1

Problem Set

Read the argument and try to identify the role of each sentence or major piece of information. Use that

1. A program instituted by a state government to raise money allows homeowners to
prepay their future property taxes at the current rate. Even if the government were
to raise the tax rate in a subsequent year, any prepaid taxes would allow the home-
owner to maintain taxes at the lower rate, lowering the overall property tax burden
over time. For this reason, homeowners should participate in the program.

2. Tay Sachs disease, a usually fatal genetic condition caused by the build-up of gan-
gliocides in nerve cells, occurs more frequently among Ashkenazi Jews than among
the general population. The age of onset is typically six months and generally results
in death by the age of four.

3. Some critics have argued that the price of food and drink at Ultralux, a restaurant, is
too high, given its quality. However, Ultralux features a beautiful interior and com-
fortable seating, and research has shown that consumers actually enjoy food and
drink more in such a setting, even when the food and drink is of comparable quality
to that served elsewhere. Thus, the food and drink at Ultralux is reasonably priced.

4. Editorial: To stem the influx of illegal immigrants, the government is planning to
construct a wall along our entire border with Country Y. This wall, however, will do
little to actually reduce the number of illegal immigrants. Because few economic op-
portunities exist in Country Y, individuals will simply develop other creative ways to
enter our nation.

5. The cutback in physical education is the primary contributing factor to North High
School's increasing failure rate on the year-end physical fitness examination. Last
year, when students participated in gym class on a daily basis, 85 percent of the
school's seniors passed the exam. This year, students had gym class twice weekly,
and only 70 percent of seniors passed the test. Clearly, fewer sessions of gym class
lead to reduced fitness.

information to write out the building block structure.

ATTAN
GMAT

Argument Structure

Chapter 1

Solutions

A program instituted by a state government to
raise money allows homeowners to prepay their
future property taxes at the current rate.

Even if the government were to raise the tax rate
in a subsequent year, any prepaid taxes would
allow the homeowner to maintain taxes at the
lower rate, lowering the overall property tax bur-
den over time.

For this reason, homeowners should participate in
the program.

This is a fact. It sounds like background, though it
could be a premise — Vm not sure yet. People can
choose to pay future taxes right now at the current
tax rate. [I'd only want to do this if it saved me
money.]

Ah, heres how it could save me money. This is a
premise. If taxes go up butVve already pre-paid,
Idont have to pay more; I got to pay at the lower
rate. [What if tax rates go down? What if I sell my
house?]

Conclusion: people should participate. Vve already
thought of a couple of reasons why it could NOT be
a good idea.

The structure is Background - Premise - Conclusion. The author concludes that people should par-
ticipate because they would save money if taxes go up.

Tay Sachs disease, a usually fatal genetic condi-
tion caused by the build-up of gangliocides in
nerve cells, occurs more frequently among Ashke-
nazi Jews than among the general population.
The age of onset is typically six months and gen-
erally results in death by the age of four.

This is a fact. Its so general that it sounds like back-
ground info, though it could be a premise.

This is also a fact — just more information about
this disease. Thats interesting. There s no conclusion
here, just two facts. Both are premises.

The structure is Premise - Premise. The argument concludes nothing. (Note: two types of questions
lack conclusions: Inference and Explain a Discrepancy. We'll discuss these later in the book.)

Some critics have argued that the price of food
and drink at Ultralux, a restaurant, is too high,
given its quality.

However, Ultralux features a beautiful interior
and comfortable seating,

"Some critics" criticize the restaurant Ultralux for
being too expensive. The language "some critics" is
often used in counterpoints; later, the author will
often tell us something else that the author or others
believe instead.

This seems to be pointing out a good thing about
Ultralux.

MANHATTAN
GMAT

Argument Structure

and research has shown that consumers actually
enjoy food and drink more in such a setting, even
when the food and drink is of comparable quality
to that served elsewhere.
Thus, the food and drink at Ultralux is reason-
ably priced.

And this tells us why the beautiful interior and
comfortable seating are beneficial. If we enjoy the
food and drink more, then perhaps we're willing to
pay more money?

This looks like a conclusion. In fact, it directly
contradicts the critics' argument in the first sentence,
which we now are sure is a counterpoint.

The structure is Counterpoint - Premise - Premise - Conclusion. The author concludes that Ultra-
lux is reasonably priced because research demonstrates that certain beneficial aspects provided by the
restaurant are valuable to the consumer.

Editorial: To stem the influx of illegal immi-
grants, the government is planning to construct a
wall along our entire border with Country Y.

This wall, however, will do little to actually re-
duce the number of illegal immigrants.

Because few economic opportunities exist in
Country Y, individuals will simply develop other
creative ways to enter our nation.

The government plans to construct a wall and
claims that this will reduce the number of illegal
immigrants. This could be the conclusion, but the
sentence also starts with the word "Editorial," imply-
ing that someone with a point of view is writing this
argument. Til have to see whether that person gives
a different opinion or claim.
"However!" Okay, whoever s writing the editorial
thinks that the government's plan is not going to
achieve its objective. This is the conclusion, so the
previous sentence must be a counterpremise.
"Because" — and here's the reason why the Editorial
writer thinks this: these illegal immigrants have no
real opportunities in their own country, so they will
just search for other ways to get into the neighboring
country.

The structure is Counterpoint - Conclusion - Premise. The author concludes that the government s
plan won't work because the people trying to immigrate illegally will just search for other ways to do so,
since they don't have many opportunities in their home country.

The cutback in physical education is the pri-
mary contributing factor to North High School's
increasing failure rate on the year-end physical
fitness examination.

Last year, when students participated in gym class
on a daily basis, 85 percent of the school's seniors
passed the exam.

This is an opinion, so it could be the conclusion. The
school isn't offering as much physical education as it
used to, and the author claims that this is causing
more students to fail a physical fitness exam.
Fact. Last year, they had gym class daily, and the
vast majority of students passed the exam.

Argument Structure

Chapter 1

This year, students had gym class twice weekly,
and only 70 percent of seniors passed the test.

Fact. This year, they had gym class less frequently,
and a smaller percentage of students passed the

exam.

Clearly, fewer sessions of gym class lead to re-
duced fitness.

Here's another claim. Having fewer gym classes
causes reduced fitness levels. Is this the conclusion:
What about the first sentence?

I need to use the Therefore Test. A = cutback in gym is causing more kids to fail the fitness exam. B = cutback

Is it the case that cutbacks in gym are causing kids to fail the exam, THEREFORE those cutbacks are causing

Or is it the case that cutbacks in gym are causing reduced fitness, THEREFORE those cutbacks are causing
more kids to fail the fitness exam?

Its the second option — first, the kids have reduced fitness, and then that causes them to fail the fitness exam.
So the first sentence is the final conclusion, and the last sentence is just an intermediate conclusion.

The structure is Final Conclusion - Premise - Premise - Intermediate Conclusion. The author con-
cludes that gym cutbacks are causing kids to fail the fitness exam because this year s seniors had fewer
gym classes, leading to reduced fitness levels which, in turn, caused more kids to fail the exam.

in gym causes reduced fitness.

reduced fitness?

GMAT

Critical Reasoning

Methodology

see

Step 1: Identify the Question
Step 2: Deconstruct the Argument
Step 3: State the Goal
Step 4: Work from Wrong to Right
How to Abbreviate

Methodology

In Chapter 1, we introduced arguments, discussed their building blocks, and examined how to "de-
construct" an argument in order to understand how the pieces of information are related. These tasks
represent the first two steps of our overall 4-step approach for any Critical Reasoning problem.

Before we dive into our 4-step process, lets discuss what we don't want to do. While there is a lot of
flexibility in how different people can work their way through the same problem, there are some ap-
proaches that are downright bad, such as this one:

1. Read the argument pretty quickly, don't take notes, don't understand the "big picture"

2. Read the question

3. Realize need to read the argument again in order to answer; re-read argument

4. Re-read question

5. Examine answers, eliminating one or several

6. Read the argument yet again

7. Eliminate another answer

8. Start checking each answer against the argument and re-reading argument

9. Repeat until one answer is left

What's the problem? That's incredibly inefficient! Inefficiency both wastes time and makes it harder for
us to answer the question correctly. There's too much going on, and that can distract us from our goal.
So what do we do instead?

Here's our 4-step approach for all CR questions:

Step 1: Identify the question.
Step 2: Deconstruct the argument.
Step 3: State the Goal.
Step 4: Work from wrong to right.

Chapter 2

Methodology

Step 1: Identify the Question

Most arguments are followed by a question (there is actually one exception; we'll discuss this later).
There are several different types of CR questions, and the wording of the question stem (the part below
the argument itself) allows us to identify which type of CR question we re about to have to answer. It's
critically important to identify that question type right away because we need to employ different kinds
of reasoning depending upon the type of question we have. We want to know, right from the start, how
best to work through the current problem.

There are three broad categories of CR questions: the Structure-based family, the Assumption-based
family, and the Evidence-based family. Each of these families contains a few distinct question types. We
also have one minor category, the Complete the Argument question type.

The Structure-Based Family

These questions all depend upon a solid understanding of the structure of the argument, similar to
what we discussed in Chapter 1. What pieces do we have and how do they fit together? There are two
types of Structure questions, both of which we'll discuss in Chapter 3:

Question Type

Sample Question Phrasing

Goal

Describe the
Role

In the argument given, the two boldface por-
tions play which of the following roles?

Identify the roles of the bold-
face portions.

Describe the
Argument

In the passage, the mayor challenges the coun-
cilmember's argument by doing which of the
following?

Describe the structure of the
argument.

The Assumption-Based Family

These questions all depend upon an understanding of the assumptions made by the author to reach a
certain conclusion. What is an assumption?

First, an assumption is something that the author does not state in the argument; for this reason, we call
assumptions unstated. An assumption is, however, something that the author must believe to be true in
order to draw the given conclusion.

We'll go into much more detail on assumptions in chapter 4 but let's look at a short example:

That car is green. Therefore, that car cannot belong to Dan.

If we re only told that the car is green, how can we know for sure that it doesn't belong to Dan? Clearly,
there's some information missing. What is the author assuming here?

The assumption: Dan does not have a green car.

MANHATTAN

GMAT

Methodology Chapter 2

If we were to insert the assumption into the argument, it would make the argument stronger:

That car is green. Dan does not have a green car. Therefore, that car cannot belong to
Dan.

In this case, it not only makes the argument stronger, it makes the argument "air tight" — we can't
argue with it! That wont always happen, but the assumption should make the argument significantly
stronger.

There are five types of Assumption questions, which we'll cover in chapters 4 and 5.

| Question Type

Sample Question Phrasing

Goal

| Assumption

The argument depends on which of the
following assumptions?

Identify an unstated assumption.

Evaluate

Which of the following must be studied in
order to evaluate the argument above?

Identify a piece of information
that would help to determine the
soundness of the conclusion.

Flaw

Which of the following indicates a flaw in
the reasoning above?

Identify something illogical in
the argument.

Strengthen

Which of the following, if true, provides
the most support for the argument above?

Strengthen the authors conclu-
sion.

Weaken

Which of the following, if true, most seri-
ously weakens the argument?

Attack the authors conclusion.

The Evidence-Based Family

These questions all lack conclusions; they consist entirely of premises! Were then asked to find some-
thing that must be true or something that eliminates a discrepancy in order to answer the question. We'll
discuss both of these question types in Chapter 6.

Question Type

Sample Question Phrasing

Goal

Inference

Which of the following can be logically
concluded from the passage above?

Identify something that must
be true based upon the given
information

j Explain a
Discrepancy

Which of the following, if true, most helps
to explain the surprising finding?

Identify something that
eliminates some discrepancy or
paradox given in the argument.

There is also a minor type called Complete the Argument. We'll discuss this type in its own separate
chapter; for now, know that you want to prioritize the three major families during your study.

MANHATTAN
GMAT

Chapter 2

Methodology

As we go through each of the families and their question types, we will learn what kind of language
signals specific question types — and that's our first big step in our 4-step approach.

Step 2: Deconstruct the Argument

Now that we've identified the family and question type, we can use that to help us deconstruct the
argument. We began to learn how to do this in the previous chapter when we labeled arguments using
the building block components. We'll learn even more about how to do this in later chapters, when we
begin discussing each question type in detail.

In order to accomplish this argument deconstruction, many people take some light notes. Some people
are able to deconstruct the argument and remember the pieces without taking notes, but most people
do take some notes. If you aren't sure which way is best for you, try taking notes for a couple of weeks;
you need some time to develop a good method and learn to work efficiently. Most people find that, the
more they practice, the less they have to write, and some people even get to the point where they only
have to write notes on the longest, most convoluted arguments.

In other words, you don't have to take notes, but don't underestimate the value of learning to take good
notes — this is a powerful tool that can help us accomplish our main goal: deconstructing arguments
efficiently and effectively.

These notes need to be neat enough to read quickly and easily, but they are also going to be heavily
abbreviated. These are not the kind of notes you take during a class, when you have to write everything
down thoroughly so that you can study for the test 3 weeks from now.

Rather, these notes will actually help us to think our way through the problem — we want to use them to
understand the structure and flow of the information. By the time we're done reading and taking notes,
we have maybe 60 to 90 seconds left. We can abbreviate extremely heavily and still remember what
those abbreviations mean in another 60 to 90 seconds.

Lets revisit the first argument that we did in Chapter 1. What might the notes look like?

The expansion of the runways at the Bay City Airport will allow for larger planes
to travel to and from Bay City. These new planes will create a large amount of
noise, a nuisance for residents who live near the airport. However, many of the
residents in this neighborhood work in construction, and the contract to expand
the runways has been awarded to a local construction company. Thus, the expan-
sion of the runways will lead to an increased quality of life for the residents of this
neighborhood.

34 MANHATTAN

GMAT

Methodology

Chapter 2

Here's one method, idea by idea:

BC rnwy T -> bigger planes -* t noise, bad for res

BUT res = constr work, local com doing work

The first line encompasses the first two sentences of the argument. Most people would probably write
down only the first sentence first:

BC rnwy T -> bigger planes

Then, as we continue reading, we realize that the second sentence followed on
from the first: those bigger planes then cause more noise. As a result, we can
just continue that same line, even though the additional information is given
in a new sentence.

If someone who hasn't read the original argument looks at our notes, then
our notes would look like nonsense — and, in fact, they should be abbreviated
enough that, if we were to re-read just the notes in a week or two (after forget-
ting the argument), we should not be able to tell what the full argument was.
If, a week later, we can reconstruct the entire argument just from our notes,
then we wrote too much down.

Let's try two more. Give yourself about 30 to 45 seconds to create notes for
the below arguments that we saw in chapter 1, incorporating the techniques
you've learned in this chapter.

1. Budget Fitness will grow its membership base by 10% in the next six
months. Budget Fitness has recently crafted a clever ad campaign that it
plans to air on several local radio stations.

TIP

When first learning this method, most
people do write too much. As part of your
review of problems, ask yourself, "Did I
write this down in the most efficient and
effective way? Did my notes make sense for
short-term use? Did I write down something
that I could've just skipped, or did I use too
many words to write something down when
I could've abbreviated more?" If you were
really off the mark, make yourself write out
the notes again in a more ideal way — and
ask yourself why this new way is better than
the old way. Now you're learning how to do
a better job on the next new problem!

MANHATTAN

GMAT

er 2 Methodology
Answer Key

Below are sample representations of notes for the two given arguments. Your notes might differ quite a
bit from the samples shown below. That's fine as long as your notes accomplish the following purposes:

• clearly delineate a conclusion (if there is one)

• demonstrate the "flow" of information (how one piece of info relates to the next, where
applicable)

• indicates contrasts or changes of direction

1. Budget Fitness will grow its membership base by 10% in the next six months. Budget
Fitness has recently crafted a clever ad campaign that it plans to air on several local radio
stations.

Sample 1 BF new ad camp to air BF member t 10% in 6 mo. ©

Sample 2 © BF mbrs > 10% 6 mos.

BF to put new ads on radio

In this argument, the conclusion was in the first sentence, so we may write down that info before we
know that it is the conclusion. The second sentence actually leads to the first sentence, so if we have
room to do so on our scrap paper, we could just write that information to the left of the conclusion. If
so, we might end up with something that looks like Sample 1. Alternatively, we might write down each
"big idea" on its own line, and then use an arrow to show that the second line leads to the first one,
similar to Sample 2.

In both cases, we label the conclusion clearly once we've found it (and, again, you can use any "this is
my conclusion" label that you want, as long as you consistently use the same label every time).

2. Last year, the Hudson Family Farm was not profitable. However, the farm will be profit-
able this year. The farm operators have planted cotton, rather than corn, in several fields.
Because cotton prices are expected to rise dramatically this year, the farm can expect
larger revenues from cotton sales than it previously earned from corn.

Sample 1 - B4, HFF not prof

✓--►© BUT will be now [why?]
+ cotton, not corn
> + cot $ 1 1 so > rev from cot than corn
[cost to grow corn?]

Sample 2

now

not cot $ > cot rev © will

prof t than corn be prof

MANHATTAN
GMAT

Methodology

In Sample 1, we ve used some pluses and minuses, along with the usual conclusion symbol, to classify
each line. A "plus" indicates a premise: something the author is using to support the conclusion. A "mi-
nus" indicates a counterpremise: something that does not support the conclusion.

Sample 2 shows us a timeline. If we ve got a future prediction, along with some past background info,
this can be an effective way to show the sequence of events. The first two sentences tell us that we ve got
a past/future situation in this argument, so we can tell at the beginning that a timeline might work.

Notice that we also added one new type of note to Sample 1: the bracketed notes [why?] and [cost to
grow corn?]. As we take notes on the argument itself, we might also want to jot down notes about what
were thinking. It wasn't profitable before, but it will be now? Why? So we're already thinking about
that as we continue to read the argument. Later, the argument says the farmers can earn more revenue
from the cotton, but the conclusion said something about profits. Profit equals revenue minus costs.
We've been given some evidence that we may be able to make more money from cotton (and even that's
debatable), but we've been told nothing about costs, so how can the argument conclude anything about
profits?

The argument told us that cotton prices are going up; it follows then, that farmers will make more
money on the same amount of cotton this year than they did on the same amount of cotton last year.
How do the prices of cotton and corn compare? We have no idea. It's entirely possible that cotton prices
have increased but are still lower than corn prices. That's a subtle point, but if you noticed that, you
might have wanted to jot down a note so that you wouldn't forget as you continued through the prob-
lem.

Chapter 2

Methodology

Step 3: State the Goal

This is a short but often overlooked step: what exactly am I trying to do when I answer this question?
What's my goal? I know what kind of question I have, I understand the argument and how it fits to-
gether now, I know my conclusion (if there is one). . . now what?

At this stage, we need to remind ourselves what it is were actually trying to do when we start attacking
the answers, and this goal depends upon the type of question that we have. Each question type requires
a certain kind of reasoning and demands certain characteristics from the correct answer. There are also
common types of wrong answer traps. Before we dive into the answers, we want to remind ourselves
(briefly) of our goal and any traps that we want to avoid. We'll learn all about these things in later
chapters.

Step 4; Work from Wrong to Right

Finally, the answer choices! On verbal in general, we're asked to find the "best" answer. We're going to
use a two-step process in order to accomplish this. First, we look through all five answers and eliminate
as many "definitely wrong" answers as we can. On this first pass through the answers, we're not actu-
ally trying to decide which is the right one, only which ones are definitely wrong.

If we only have one answer left, great; we're done. If we have two or more answers left, then we compare
those remaining answers.

Why do we do it this way? By definition, finding the best answer is a comparison; if I spot a tempting
answer, I can't know whether it's the best one until I've seen all of the others. It's most efficient to dump
all of the "no way" answers as fast as we can, and then directly compare the remaining, more tempting
answers.

Finally, we have one last important rule to remember for verbal questions: when we've narrowed down
to two answers, we should look at each answer and compare the two once more, but then we should
pick and move on. Going back and forth multiple times is a waste of time — either we know it after
comparing the first time or we don't.

As we go through and assess these answers, it's critical to keep track of our thinking — we're actually
going to track what we think about each of the five answers as we go. There are two big decisions to
make in terms of how you choose to do this.

MANHATTAN
GMAT

Methodology

Chapter 2

Decision #1: How do I write down ABCDE?

What to Do

Pros

Cons

Write ABCDE for each
question

Can write directly on each letter;
can keep letters with notes about
argument

Have to write 41 separate times

Write ABCDE at the top
of the page, then move to a
new line for each question

Only have to write once for each
page (several times for entire test)

Have to keep track "below" each
letter; notes for problem might not
be right next to answer tracking
row

Option 1 (write for each question) might look like this:

notes
notes

SAB^DE

notes
notes

Option 2 (write once per page) might look like the below, where the first question (a Weaken) is an-
swered in the first row and the second question (a Strengthen) is answered in the second row. Remem-
ber that the scrap paper will be graph paper, so there will already be lines built-in to separate the five
answer choices.

notes

MANHATTAN
GMAT

Methodology

Decision #2: What symbols will I use to keep track of my thoughts?

We need four symbols in order to keep track of our thoughts on the answers; you can use any symbols
you prefer as long as you consistently use the same symbols to mean the same things:

x or/

Definitely wrong

Maybe

I have no idea

This is it!

Let s try all of this on an actual problem.

Over the past decade, many companies have begun using automated telephone
services; callers hear a machine-generated voice and are able to select options us-
ing the numbers on the telephone keypad. Research shows that callers are more
patient when the machine-generated voice is that of a woman. Thus, smaller
companies that cannot afford an automated service should consider hiring
women, rather than men, to interact with customers by phone.

Which of the following, if true, would be most damaging to the conclusion above?

(A) Automated telephone services are becoming cheaper and cheaper every
year.

(B) Patient customers tend to order more products and return fewer products
than impatient customers.

(C) A separate study indicated that the extra patience exhibited by callers is
limited to interactions with an automated system.

(D) Some customers prefer automated systems to talking with a live person.

(E) On average, callers are only slightly more patient when interacting with a
female voice, rather than a male voice, in an automated telephone system.

How did you do with each step? Did you identify the question type? Do you feel comfortable with your
notes, and did you identify the conclusion (if there is one)? Did you remember to state the goal (briefly)
before looking at the answers? Did you use the 2-pass process to assess the answer choices?

Here's how someone might work through the above problem. We'll show each of the four steps sepa-
rately. The first column will show the relevant text from the problem. The second column will show
what we might write on the scrap paper. The third column will show what we might be thinking while
working on the problem.

Methodology

Chapt

Step 1 : Identify the Question

Which of the following, if true,
would be most damaging to the
conclusion above?

A B C D E

Step 2: Deconstruct the argument

Over the past decade, many
companies have begun using
automated telephone services;
callers hear a machine-generated
voice and are able to select op-
tions using the numbers on the
telephone keypad.
Research shows that callers are
more patient when the machine-
generated voice is that of a
woman.

Thus, smaller companies that
cannot afford an automated
service should consider hiring
women, rather than men, to in-
teract with customers by phone.

lOy: corns use auto
phone

R: female =
t patience

Small com -» use
women phone

"most damaging to the conclusion"
means this is a Weaken. I need to find
the conclusion, and I need to think
about what flaws or gaps might exist be-
tween the premises and the conclusion.

Sounds like background, but V 11 jot
down a note anyway.

This is describing what an automated
phone system is; I probably dont need to
write that down.

This is a fact, not a claim, so it has to be
either a premise or counterpremise. Its
probably a premise, since there s only one
sentence left.

This is the only claim, so its the con-
clusion. Now I can go back and add a
© to the conclusion in my notes and a
+ to the premise.

The final notes might look something like this:

W ABCDE

lOy: corns use auto phone

+ R: female = t patience

Your notes might look very different from the above notes. That's perfectly fine as long as your notes
convey the basic flow of information clearly and concisely. Your notes also need to identify the question
type, and you need some mechanism by which to track your answers.

GMAT

er2

Methodology

Step 3: State the Goal.

The conclusion is that small companies should hire women to answer the phones, because callers are more
patient when hearing automated female voices.

I need to weaken the conclusion, so that would mean there's some reason why companies might not be better
off hiring women to answer the phones.

[Hmm. The evidence is about automated female voices, while the conclusion is about real women. Is there
any kind of disconnect there?]

First, we briefly restate the core of the argument — the conclusion and the main reasoning that supports
that conclusion. Then we articulate what kind of answer would accomplish our goal — in this case, to
weaken the conclusion. We may also happen to notice significant discrepancies, and we can articulate
those at this stage as well.

Step 4: Work from wrong to right

Now, were ready to attack the answers.

(A) Automated telephone ser- ABCDE
vices are becoming cheaper and
cheaper every year.

(B) Patient customers tend to ABCDE
order more products and return

fewer products than impatient
customers.

by callers is limited to interac-
tions with an automated system.

(D) Some customers prefer auto- A 8 C B E
mated systems to talking with a
live person.

The conclusion discusses what companies should
do when they can t afford automated services. If
the service becomes cheap enough that a particu-
lar company can buy it, that company no longer
has to worry about whether to hire women or
men to answer the phones.
This is a good reason for the company to do
whatever it can to keep its customers in a patient
mood. If anything, that would strengthen the
argument.

Hmm. This creates a distinction between auto-
mated and live voices. . . I was wondering earlier
whether that might be the disconnect. There
doesnt seem to be any evidence now that a live
female voice will make callers more patient. Keep
this one in.

Presumably these customers would be more
patient with an automated system. . . oh, but
this argument is only about those companies who
cant afford the system and are using real people.
Nope, this isn't it.

MANHATTAN
GMAT

Methodology

Chapter 2

(E) On average, callers are only
slightly more patient when
interacting with a female voice,
rather than a male voice, in an
automated telephone system.

A fi @ © E This one seems to be telling me there isn't a huge
difference between male and female voices — but
there is still a small positive effect for female voic-
es. If anything, this strengthens the argument;
after all y as a small business owner, I'll take any
necessary steps that will get me more business! I
only have one answer left, so C is the answer.

lilii

How to Abbreviate

A clear, consistent shorthand (abbreviation) method will help us to take notes efficiently and spend
more of our mental energy focused on how the argument works (rather than how to write down a par-
ticular piece of information).

The chart below contains some symbols and abbreviations that are especially useful for Critical Reason-
ing. As you study, make sure to develop your own.

Increase / more / high

Decrease / less / low

Causes / leads to / results in

Was caused by

Greater than / more than /

Less than / smaller

< ;

majority

than / minority

Equals / correlates with

Number

Price / dollar amount

Percent

% \

Change

Women / Men

W/M

Best / most effective

★

Worst / least effective

Attribution (e.g. the Mayor
said. . .)

e.g. M:

Like / dislike

©/©

Future / prediction (something
will happen, someone plans to
do something)

Century (e.g., 20th
century)

e.g. 20c

Time

However / altnough
/ etc

BUT

years

conclusion

your own thoughts (not in the
argument)

[your own thoughts
in brackets]

Profit, Revenue, Cost

P = R-C

premise

+ (plus)

counterpremise

- (minus)

MANHATTAN
GMAT

Methodology

For very large increases or decreases, a very large majority or very small minority, and so on, double the
symbol. For example, for a very large increase in the number of employees, write 1 1 # emp.

For the profit formula, do write out the whole formula even if the argument mentions only profit, or
only profit and either revenues or costs. All three variables go together (and that fact is often the weak
point for a question that mentions profit).

For any names, unfamiliar "big" words, or other unusual words, simply use the first letter of the name
or word. In traditional note-taking, that wouldn't be adequate, but we only need to remember for about
90 seconds, and a single-letter abbreviation is sufficient to remember for 90 seconds.

Takeaways

Our 4-step approach for all CR Questions is:

Step 1 ; Identify the question,

• we'll learn how to do this in later chapters

• the question type tells us what kind of information we expect to find in the argument and
what kind of reasoning help to answer the question

Step 2: Deconstruct the argument

• break the argument down into its building blocks

• take very abbreviated notes showing both the details and the "flow" of the information

Step 3: State the Goal,

• very briefly articulate your goal based upon this question type (again, we'll learn the goals
for each type in later chapters)

Step 4: Work from wrong to right

• plan to go through the answers twice

• on the first pass, focus on eliminating anything that is definitely wrong; leave everything
else in

• on the second pass, compare any choices that remain, then pick

Know how you're going to keep track of your answers on your scrap paper. First, decide whether to have
a separate ABCDE grid for each problem or whether to use the "write once per page" method described
earlier in the chapter. Second, make sure you have four consistent symbols for these four labels: defi-
nitely wrong; maybe; I have no idea; and this is it!

Methodology

Problem Set

Read the argument and try to identify the role of each sentence or major piece of information. Take ab-
breviated notes for the argument. Use that information to write out the building block structure.

1. A series of research studies has reported that flaxseed oil can have a beneficial effect
in reducing tumor growth in mice, particularly the kind of tumor found in human
postmenopausal breast cancer. Thus, flaxseed oil should be recommended as an ad-
dition to the diets of all postmenopausal women.

2. During the past thirty years, the percentage of the population that smokes ciga-
rettes has consistently declined. During the same time period, however, the number
of lung cancer deaths attributed to smoking cigarettes has increased.

3. The Chinese white dolphin is a territorial animal that rarely strays far from its habitat
in the Pearl River Delta. In recent years, increasing industrial and agricultural runoff
to the Delta's waters has caused many white dolphins to perish before they reach
breeding age. Unless legislation is enacted to ensure there is no further decline in
the Delta's water quality, the Chinese white dolphin will become extinct.

4. Most doctors recommend consuming alcohol only in moderation, since the ex-
cessive intake of alcohol has been linked to several diseases of the liver. Drinking
alcohol is no more dangerous for the liver, however, than abstaining from alcohol
entirely. Last year, more nondrinkers than drinkers were diagnosed with liver failure.

5. To increase the productivity of the country's workforce, the government should
introduce new food guidelines that recommend a vegetarian diet. A study of
thousands of men and women revealed that those who stick to a vegetarian diet
have IQs that are around five points higher than those who regularly eat meat. The
vegetarians were also more likely to have earned advanced degrees and hold high-
paying jobs.

Methodology

Chapter 2

Solutions

Note: the sample notes show in the answer key represent only one example of how someone might take
ntoes. Just make sure that your notes are legible, very concise, and convey the main points in a manner
that makes sense to you.

Argument

A series of research studies has reported
that flaxseed oil can have a beneficial ef-
fect in reducing tumor growth in mice,
particularly the kind of tumor found in
human postmenopausal breast cancer.

Thus, flaxseed oil should be recom-
mended as an addition to the diets of all
postmenopausal women.

Notes

R: Flax helps 1 tumor mice
esp PM BC

R: flax helps 1 tumor mice
esp BC

1 PM women shd take flax

Thoughts

This is a fact. It's
either background or a
premise.

Definitely the conclu-

sion.

The structure of this argument is Premise - Conclusion.

Argument

During the past thirty years, the
percentage of the population that
smokes cigarettes has consistently
declined.

During the same time period,
however, the number of lung cancer
deaths attributed to smoking ciga-
rettes has increased.

Notes

30y: % pop smoke cig I steady

30y: % pop smoke cig I steady
same P: # LC dead from cig t

Thoughts

This is a fact. Its
either background or a
premise.

Another fact, so an-
other premise. There
isn't a conclusion.

The structure of this argument is Premise - Premise.

MANHATTAN 47
GMAT

Chapter 2

Methodology

Argument

The Chinese white dolphin is a ter-
ritorial animal that rarely strays far
from its habitat in the Pearl River
Delta.

In recent years, increasing indus-
trial and agricultural runoff to the
Delta s waters has caused many
white dolphins to perish before they
reach breeding age.

Unless legislation is enacted to
ensure there is no further decline
in the Deltas water quality, the
Chinese white dolphin will become
extinct.

Notes

CWD stays in PRD

The structure of this argument is Premise - Premise - Conclusion.

Argument

Most doctors recommend con-
suming alcohol only in modera-
tion, since the excessive intake
of alcohol has been linked to
several diseases of the liver.

Drinking alcohol is no more
dangerous for the liver, howev-
er, than abstaining from alcohol
entirely.

Last year, more nondrinkers
than drinkers were diagnosed
with liver failure.

Notes

Drs rec I ale be t ale liver
dis

Drs rec I ale be T ale liver
dis

@ drink not worse than abstain

Drs rec I ale be T ale liver
dis

drink not t bad than abstain
ly: >nondrink had liv dis

CWD stays in PRD

rent: ind + ag in PRD
CWD die b4 breed

CWD stays in PRD

rent: ind + ag in PRD ->
CWD die b4 breed

IF govt doesn't fix H20 -*
CWD extinct

Thoughts

This is a fact. It's either
background or a premise.

This is also a fact but
is more like a premise
because it feels like it could
build to a conclusion.

And here's the conclusion.

[Note: H20 here is an ab-
breviation for water, based
on the chemical formula
H 2 O.J

Thoughts

This is a fact. Its either back-
ground or a premise.

Oh, this has the word "how-
ever!" The last sentence was a
counterpremise, and this one
sounds like the conclusion.

This supports the previous
sentence; it's a premise. [It also
seems pretty flawed. What
percentage of nondrinkers vs.
drinkers had liver disease?]

The structure of this argument is Counterpremise - Conclusion - Premise.

GMAT

Methodology

Chapter 2

Argument

To increase the productivity of
the country's workforce, the
government should introduce
new food guidelines that rec-
ommend a vegetarian diet.

A study of thousands of men
and women revealed that those
who stick to a vegetarian diet
have IQs that are around five
points higher than those who
regularly eat meat.

The vegetarians were also more
likely to have earned advanced
degrees and hold high-paying
jobs.

Notes

govt shd rec veg to t wrkr
prod

govt shd rec veg to T wrkr
prod

S: veg t IQ than non-veg

govt shd rec veg to t wrkr
prod

S: veg t IQ than non-veg
veg > better schl and high pay

Thoughts

This is definitely a claim.
It sounds like a conclusion,
though Idont know for sure
yet.

This is a fact — the results of a
study. It also supports the claim
above, so it's a premise.

This is another premise sup-
porting the first sentence.

The structure of this argument is Conclusion - Premise - Premise.

GMAT

Critical Reasoning

Structure-Based Family

On 7& Chapter. . .

Describe the Role
Describe the Argument

Structure-Based Family

In the first two chapters, we introduced arguments, examined the building blocks used to construct
them, and learned the overall 4-step approach to tackling any Critical Reasoning question. We also
introduced the main types of questions found on the test. Here's our 4-step approach:

Step 1: Identify the question.

Step 2: Deconstruct the argument.

Step 3: State the Goal.

Step 4: Work from wrong to right.

Now, we're going to begin tackling the first of our three main Critical Reasoning Families: the Struc-
ture-Based questions. As the name implies, these questions depend upon our ability to understand the
structure of the argument. What kinds of building blocks are present in the argument? Which piece
leads to which piece? What is the purpose of each piece of info — what role does it play?

There are two main Structure question types: Describe the Role and Describe the Argument.

Describe the Role

Of the two types, Describe the Role (or Role, for short) is more common. These questions present a
standard argument, but one or two portions of that argument are presented in boldface font. We are
asked to describe the role each portion of boldface font plays.

What does "role" mean? We actually already studied this. The "role" is just another name for building
block. A particular bolded portion could be a premise, a conclusion, a counterpremise, an intermediate
conclusion, or background information. It could also be a counter-conclusion or opposing conclusion,

er 3

Structure-Based Family

something we didn't discuss earlier. An opposing conclusion is simply a conclusion that goes against the
authors main conclusion.

These question types are easy to identify because one or two statements (usually two) will be presented
in bold font, and the question stem will include the word "boldface."

Our task here is to determine the role that each boldface statement plays in the argument. We're going
to discuss two possible methods. The Primary Method will always work, but it's more complicated and
time-consuming to use. The Secondary Method will allow us to narrow down answer choices more
easily but may not allow us to get all the way to one answer — that is, we may have to guess from a nar-
rowed set of answers.

Primary Method

There are three possible roles:

(P) The statement in boldface is a PREMISE (it supports the author's
conclusion)

(X) The statement in boldface is SOMETHING ELSE (this might be a
counterpremise, background information, acknowledgement of a weak-
ness in the argument. . .)

Strategy Tip: Labels C and P are considered to be "on the same side"
(because both are part of the author's argument).

Strategy Tip: Label X is considered to be "on the opposite side" of labels
C and P, because label X does not support the author's argument.

In our notes, we'll classify each statement using the labels C, P, or X, as described above. When we
evaluate the answer choices, we'll look for matching language based upon our labels.

How would that work? Let's say that we've decided to label the first boldface statement with an X and
the second boldface with a C. Then we check our answers for an XC pattern.

The answer choices are the most difficult part of Structure questions in general because they are written
in an abstract form. For example, an answer might read:

(A) The first [boldface statement] is evidence that has been used to weaken
a claim made by the argument; the second [boldface statement] is that
claim.

The first half of that sentence is quite convoluted. Let's start with the most basic piece: a building block.
There is a claim made by the argument; the claim is the conclusion. This first half says that the first

MANHATTAN
GMAT

Structure-Based Family

Chapters

boldface weakens the conclusion. Something used to weaken the conclusion is a counterpremise. If we
labeled the first boldface statement with an X, then this might be the right answer.

The second half of the sentence is more straightforward but includes a structure that is commonly used
to try to confuse us. It refers back to something that was said in the first half of the answer choice. In
this case, the second half refers to "that claim." It s not just talking about any claim here; its talking
about the same claim that was mentioned in the first half of the sentence. The second half is describing
the conclusion; if we labeled the second boldface statement a C, then this might be the right answer.

Great! We wanted an XC combo (in that order), and we just found an answer choice that gives us an
XC combo. We re done!

If we can use the above method accurately, we will be able to eliminate the 4 wrong answers and get to
the right answer. We might struggle to do that, though, or it might take too much time. Our Second-
ary Method allows us to get rid of some answers more quickly before taking a guess from among the
remaining answers.

Secondary Method

There are three possible roles:

(O) The statement in boldface is an OPINION (but not the conclusion).

Strategy Tip: Check for the conclusion first. Only label something an O
if it is NOT the conclusion.

How would this work on our answer choice from above? This time, lets say that we have labeled the
first boldface from our argument with an F and the second boldface with a O (opinion but not conclu-
sion). Next, we check the answers.

(A) The first [boldface statement] is evidence that has been used to weaken
a claim made by the argument; the second [boldface statement] is that
claim.

The word "evidence" typically indicates a fact, not an opinion, so the first half is likely describing an F
label. The second half is still describing the conclusion, so it would receive a label of C.

That doesn't match. We re looking for an FO combo, but this answer gives us an FC combo. Eliminate it.

MANHATTAN
GMAT

Chapter 3

Structure-Based Family

Common Trap Answers

The most tempting trap answers on Role questions tend to be "off by just one word, and that word is
usually at the end of the sentence. For instance, let s imagine that we've decided the first boldface is a
premise in support of the author's conclusion — in other words, a P. A tempting wrong answer might
read:

(A) The first [boldface statement] provides evidence in support of the position
that the argument seeks to reject.

Every word of that answer matches what we want to find with the exception of the very last word, "re-
ject." In fact, if we changed that one word, the answer would be correct:

(A) The first [boldface statement] provides evidence in support of the position
that the argument seeks to establish.

The first version of the answer choice says that the first boldface is a premise in support of some
counterconclxxsion. That's an X label, not a P. The second version says that the first boldface is a premise
in support of the author's conclusion, and that is, indeed, a P label. If we're not reading every word very
carefully, we may pick the first version without even realizing that it's an X, not a P!

MANHATTAN
GMAT

Structure-Based Family

Chapter 3

Putting It All Together

Let s try a full example:

Mathematician: Recently, Zubin Ghosh made headlines when he was recognized
to have solved the Hilbert Conjecture. Ghosh posted his work on the internet,
rather than submitting it to established journals. In fact, he has no job, let alone
a university position; he lives alone and has refused all acclaim. In reporting on
Ghosh, the press unfortunately has reinforced the popular view that mathemati-
cians are antisocial loners. But mathematicians clearly form a tightly knit com-
munity, frequently collaborating on important efforts; indeed, teams of research-
ers are working together to extend Ghosh's findings.

In the argument above, the two portions in boldface play which of the following
roles?

(A) The first is an observation the author makes to illustrate a social pattern; the
second is a generalization of that pattern.

(B) The first is evidence in favor of the popular view expressed in the argument;
the second is a brief restatement of that view.

(C) The first is a specific example of a generalization that the author contradicts;
the second is a reiteration of that generalization.

(D) The first is a specific counterexample to a generalization that the author as-
serts; the second is that generalization.

(E) The first is a judgment that counters the primary assertion expressed in the
argument; the second is a circumstance on which that judgment is based.

GMAT

Chapter 3

Structure-Based Family

Step 1 : Identify the question.

In the argument above, the two R
portions in boldface play which
of the following roles?

A B C D E

This is a Role question. The argu-
ment contains bold font, and the
question stem contains the words
"boldface" and "role."

Step 2; Deconstruct the argument

Mathematician: Recently, Zubin
Ghosh made headlines when he
was recognized to have solved
the Hilbert Conjecture.
Ghosh simply posted his work
on the internet, rather than
submitting it to established
journals.

In fact, he has no job, let alone
a university position; he lives
alone and has refused all ac-
claim.

In reporting on Ghosh, the press
unfortunately has reinforced the
popular view that mathemati-
cians are antisocial loners.

But mathematicians clearly
form a tightly knit commu-
nity, frequently collaborating
on important efforts; indeed,
teams of researchers are work-
ing together to extend Ghosh s
findings.

R A B C D E
M: ZG slvdHC

A B C D E

M: ZG slvdHC
ZG pub Int

R A B C D E

M:ZG slvdHC

ZG pub Int

no job, not math guy

*r~ aTcTd e

M: ZG slvdHC
ZG pub Int
no job, not math guy
R: ZG, math = loners

A B C D E

A past fact — this is likely back-
ground. Still, F 11 jot down a note.

Sounds like more background.

Here's the first boldface. He's not
\ a mathematician; that's surpris-
| ing. Still, I don't know what the
j conclusion is, so I don't know

what role this sentence ^ playing.

j M: ZG slvdHC
ZG pub Int
no job, not math guy
R: ZG, math = loners
!) BUT math = commun,
collab

R A B C D E

M: ZG slvdHC
ZG pub Int
(^)no job, not math guy
R: ZG, math = loners
©BUT math = commun, collab

So the first boldface is "evi-
dence" of "the popular view" that
mathematicians are loners. . . but
the sentence also uses the word
"unfortunately" so it sounds like
the author doesn't agree. . .

/ was right; the author disagrees.
The author's conclusion is this
second boldface statement, so I can
label it with a ©.

Now, what about that first
boldface statement? It's not the
conclusion, and it doesn't support
the conclusion, so it must be an X:
\ Something Else.

MANHATTAN
GMAT

Structure-Based Family

Chapter 3

Step 3: State the Goal

The first boldface statement is an X; that is, it is neither the conclusion nor a premise. In this case, it sup-
ports the alternate point of view, so we can call it a counterpremise. It goes against the conclusion. The second
boldface statement is a C; it is the authors conclusion.

Whatever answer I find should describe the first statement as something consistent with an X label and should
describe the second statement as something consistent with a C label. Tm looking for an XC combo, and those
two labels are on "opposite sides. "

Step 4: Work from wrong to right.

(A) The first is an obser-
vation the author makes
to illustrate a social
pattern; the second is a
generalization of that
pattern.

(B) The first is evidence
in favor of the popular
view expressed in the
argument; the second
is a brief restatement of
that view.

R A B C D E

M: ZG slvd HC

ZG pub Int
)no job, not math guy

R: ZG, math = loners
)BUT math = commun,

collab

A © C D E

M: ZG slvdHC

ZG pub Int
)no job, not math guy

R: ZG, math = loners
)BUT math = commun,

collab

example of a general-
ization that the author
contradicts; the second
is a reiteration of that
generalization.

M: ZG slvd HC

ZG pub Int
@no job, not math guy

R: ZG, math = loners
©BUT math = commun,

collab

Hmm. I'm not 100% sure what they mean
by "illustrate a social pattern, " but I can tell
that the description of the two statements here
makes them sound like they're on the same
"side" — the first illustrates something, and
the second generalizes that same thing. I want
an "opposite sides" answer.

; The first supports a popular view... okay,
maybe. You could call the press view the
popular view. Oh, but the second doesnt
restate that view; the second goes against that
view. These two are on the same side again,
and I want an "opposite sides" answer.

"The first is a <something> that the author
contradicts. " The <something> part confuses
me, but I agree that the author contradicts
the first one; this is a good description of
this " label X" statement. Hmm. The second
repeats "that generalization" — the same one
mentioned for the first statement? No, Tm
looking for opposite sides.

GMAT

Structure-Based Family

(D) The first is a spe-
cific counterexample
to a generalization that
the author asserts; the
second is that general-
ization.

AB6DE

(E) The first is a judg-
ment that counters
the primary assertion
expressed in the argu-
ment; the second is a
circumstance on which
that judgment is based.

M: ZG slvdHC

ZG pub Int
(^)no job, not math guy

R: ZG, math = loners
©BUT math = commun,

collab

R AB€®E

M: ZG slvd HC

ZG pub Int
(^)no job, not math guy

R: ZG, math = loners
©BUT math = commun,

collab

The first is a counterexample to something
the author says? Yes, that accurately describes
a " label X." The second is "that generaliza-
tion?" I crossed off the last one for this same
language. But wait. . . which generalization is
this referring to this time? Oh, a generaliza-
tion that the author asserts: that's the conclu-
sion, which is a "label C." Leave this answer

tn.

| "Counters" language — yes, the first statement
does counter the conclusion, which is consis-
tent with the label X. "That judgment" = the
first boldface. The second is not something on
which the first one is based — that would be
same side, and I want opposite sides.

Takeaways for Describe the Role Questions

We recognize this question type by the boldface font in the argument and the use of the word "bold-
face" in the question stem. The question stem will also typically use the word "role" or a synonym. We
will usually have two boldface statements, but sometimes there will be only one.

Our goal is to identify the specific role, or building block category, of each boldface statement. Our
primary method involves splitting the building blocks into three categories:

C: The conclusion

P: A premise supporting the conclusion
X: Something other than C or P

If needed, we can also try a secondary method that will allow us to make an educated guess if were
short on time or get stuck:

C: The conclusion
F: A fact

O: An opinion that is not the conclusion

The most tempting trap answers will be "off" by just one or two words, often at the end of the sentence
or phrase. We have to read very carefully all the way to the end in order not to fall for this trap.

Structure-Based Family Chapter 3

Describe the Argument

Describe the Argument questions can be similar to Role questions in that Describe the Argument ques-
tions usually also offer "abstract" answer choices that explicitly discuss the structure of the argument,
including referring to the various building blocks (conclusions, premises, and so on). The majority of
these Argument questions will offer two competing points of view and ask us, for example, how one
person responds to the argument made by the other person.

Important note: other question types can also be presented in this "two people speaking" format — the
mere existence of two speakers does not make the problem a Describe the Argument problem. Its always
necessary to identify the question type based upon the question stem.

A minority of these questions will instead offer just one point of view and ask us how the author of that
argument develops his or her point of view.

Common question formulations include:

Bill responds to Sally s argument by

Bill challenges Sally's argument by

The author develops the argument by doing which of the following?
These all indicate that we have a Develop the Argument question.

Our task here is to determine the manner in which a particular part of the text was constructed. If the
second person disagrees with the first person, for example, we may be asked to explain how the second
person disagrees, and possible answers might involve providing alternate evidence that contradicts the
first person's claim, demonstrating that some evidence used by the first person is invalid or flawed (or
simply questioning the accuracy of that evidence), introducing a new piece of information that the first
person failed to consider, and so on.

If the argument is presented in two parts, with one person presenting an argument and the second
replying, then the first person's text is a complete argument that we need to read and diagram just as we
do any argument. It's critically important to label each piece of information in the first speaker's argu-
ment. Next, we examine the response and figure out which piece of the argument the response attacks.
Ultimately, the attack is designed to find fault with the conclusion, but don't assume that the second
person is attacking the conclusion directly. Tearing down any piece of the argument would ultimately
undermine the conclusion, so find the piece that the second person most directly attacks.

MANHATTAN
GMAT

Chapter 3

Structure-Based Family

Here's an example:

Bill: I need to learn the names of 100 muscles for the anatomy exam in two hours.
I've just memorized 5 of them in 5 minutes, so I only need 95 more minutes to
study. Therefore, 111 have plenty of time to memorize everything and get a perfect
score on the test.

Sally: Are you sure? Perhaps the more you memorize, the harder it gets.

Sally responds to Bill by

Were not going to look at answer choices yet for this one. What is Bill s argument? What is his conclu-
sion, and how does he support it?

must learn 100 names in 2h

mem 5 in 5m, so need 95m

[have >95m]

Which part does Sally attack? Does she attack the conclusion directly? No, but her words certainly cast
doubt on Bill's eventual conclusion. She attacks Bills assumption that he can maintain the same rate of
learning, 1 name every minute, for all 100 words. He doesn't explicitly state that he can maintain that
rate, but he clearly believes it to be true in order to say that he needs only 95 more minutes. The correct
answer might read something like:

Sally calls into question an assumption Bill makes about the efficacy of his plan.

This answer addresses the appropriate part of the argument — an assumption that Bill makes about his
plan. An incorrect answer might look something like:

Sally introduces new evidence that contradicts one of Bill's premises.

Sally does say something new, but does it rise to the level of evidence? She only suggests that his memo-
rization rate might not be constant; she doesn't prove that it is not. While we might be able to argue
that the word "evidence" is okay, the word "contradicts" clearly takes things too far. Sally does not de-
finitively contradict Bill's premise that he will need only 95 more minutes; rather, she raises a question
as to whether he really can memorize the words in only 95 minutes.

We probably won't be able to anticipate the exact abstract language of the correct answer, but if we can
identify the part of the argument addressed, then we are in a much better position to find the appropri-
ate "matching" language in the correct answer.

MANHATTAN
GMAT

Structure-Based Family

Chapter 3

Common Trap Answers

The most tempting trap answers on Describe the Argument questions will be similar to those on Role
questions: most of the answer is fine, but one or two words will throw the answer "off."

In addition, because most of these arguments will consist of a second person objecting to something the
first person says, it will always be tempting to choose an answer that indicates that Sally rejects Bills

conclusion. It is the case, ultimately, that Sally s comment is going to weaken Bill s conclusion somehow,
but she may not directly attack the conclusion — and the question asks us to articulate what she attacks
directly.

Let s try a full example:

Mayor: The recycling program costs us nearly $1 million to operate every year,
and our budget shortfall this year is projected to be $5 million. We need to cut the
recycling program in order to help balance the budget.

Consumer Advocate: It costs the city more to throw something out than to recycle
it.

The consumer advocate responds to the mayor by

(A) establishing that the mayor's figures were incorrectly calculated

(B) accepting the mayor's conclusion but questioning the legality of the plan

(D) introducing a new piece of information that calls into question the validity of
the mayor's conclusion

(E) pointing out that the mayor has not adequately considered the potential
causes and effects of the budget shortfall

MANHATTAN
GMAT

Chapter 3

Structure-Based Family

Step 1 : Identify the question.

The consumer advocate re-
sponds to the mayor by

Step 2: Deconstruct the argument

This is a Describe the Argument
question. Two people are talking,
and I have to explain how one
responds to the other.

Mayor: The recycling program
costs us nearly $1 million to op-
erate everv vear. and our budget
shortfall this year is projected to
be $5 million.

DA A B C D E

M: R cost $lm; this yr $5m
short

The mayor is stating a couple of
facts — recycling costs $lm and
they're voinv to miss their budget
by $5m.

We need to cut the recycling
program in order to help bal-
ance the budget.

DA A B C D E

M: R cost $lm; this yr $5m
short -» cut R -> bal budg ©

So the mayor suggests that they
should cut the R program in or-
der to help balance the budget.

Consumer Advocate: It costs the
city more to throw something
out than to recycle it.

DA A B C D E

M: R cost $lm; this yr $5m
short -» cut R -* bal budg ©

CA: throw away costs > R

That's interesting The CA
says that it costs even more to
throw something out. Why does
this matter? If you cant recycle
something, what are you going
to do with it instead? Probably
throw it out.

Step 3: State the Goal

For Describe the Argument questions I have to address how some part of the argument is made. In this case,
I have to describe how the CA responds to the M. First, it sounds like the CA thinks that the Ms plan isn't
going to work. The CA doesn't say so directly, but does say that throwing stuff out is more costly than recycling
it. If that's true, then the plan to cut the recycling program just got a bit worse — it might not actually achieve
the ultimate goal, which is to save money (to help balance the budget).

The answer I find should indicate that the CA disagrees with the M, and specifically the CA disagrees as to
whether the suggested action (cutting the R program) will result in the desired outcome (saving money, helping
to balance the budget).

MANHATTAN
GMAT

Structure-Based Family

Chapters

Step 4: Work from wrong to right

(A) establishing that
the mayors figures were
incorrectly calculated

(B) accepting the
mayor s conclusion but
questioning the legality
of the plan

| way that reduces the
i validity of the mayors
claim

(D) introducing a new
piece of information
that calls into ques-

j tion the validity of the
mayors conclusion

(E) pointing out that
the mayor has not
adequately considered
the potential causes and
effects of the budget
shortfall

A B C D E

M: R cost $lm; this yr
$5m short -> cut R -» bal
budg©

CA: throw away costs > R
DA AfiCDE

M: R cost $lm; this yr
$5m short -» cut R -> bal
budg©

CA: throw away costs > R
DA AfiCDE

M: R cost $lm; this yr
$5m short -> cut R -» bal
budg©

CA: throw away costs > R
DA A fi € D E

M: R cost $lm; this yr
$5m short -> cut R bal
budg©

CA: throw away costs > R
DA Afi€©E

M: R cost $lm; this yr
$5m short -» cut R -» bal
budg©

CA: throw away costs > R

The CA doesn't say anything about the
mayors figures — in fact, the CA doesn't
dispute the mayors evidence at all. Rather,
the CA attacks the mayors assumption that
cutting the program will lead to balancing
the budget.

The CA doesn't accept the conclusion, nor
does the CA say anything about legality.
Rather, the CA questions whether the plan
will really lead to saving money.

Hmm. Maybe. The CA does reduce the valid-
ity of the mayors claim. Fm not 100% sure
what "interpreting the evidence" means. Til
leave this in for now.

The CA does call the mayors conclusion into
question, yes. Oh, I see — this one is better
than answer C because the CA does introduce
a new piece of info (that it costs more to throw
something away).

This one is tricky. It's true that the mayor
hasn 't fully considered the potential effects of
the plan to cut the recycling program — but
that's not what this choice says. It talks about
the causes and effects of the budget shortfall.

til

GMAT

Chapter 3

Structure-Based Family

Takeaways for Describe the Argument Questions

We recognize this question type by the question stem (most commonly asking us how one person
"responds" or "objects" to something that another person said), and by the "abstract" answer choices
that address the role of the information (claim or conclusion, evidence or premise, and so on). We will
be asked to address the role of a particular sentence or statement within the conversation (usually the
respondent s statement, if there are two people talking).

Our goal is to identify the specific role played by the statement about which were asked. Most of the
time, that role will have something to do with calling into question a premise, assumption, or conclu-
sion made by the first person. That can be done by directly attacking what the first person said, or by
introducing new information that undermines the first person s argument.

MANHATTAN
GMAT

Structure-Based Family

Chapter3

Problem Set

1. Ad Revenues

Media Critic: Network executives allege that television viewership is decreasing
due to the availability of television programs on other platforms, such as the in-
ternet and mobile devices. These executives claim that declining viewership will
cause advertising revenue to fall and networks will thus be unable to spend
the large sums necessary to produce high-quality programming. That devel-
opment in turn, will lead to a dearth of programming for the very devices that
cannibalized television's audience. However, research shows that users of alterna-
tive platforms are exposed to new programs and, as a result, actually increase
the number of hours per week that they watch television. This demonstrates
that alternative platforms will not prevent networks from increasing advertising
revenue.

The portions in boldface play which of the following roles in the media critic's
argument?

(A) The first is an inevitable trend that weighs against the critic's claim; the sec-
ond is that claim.

(B) The first is a prediction that is challenged by the argument; the second is a
finding upon which the argument depends.

(D) The first acknowledges a position that the network executives accept as
true; the second is a consequence of that position.

(E) The first opposes the critic's claim through an analogy; the second outlines a
scenario in which that claim will not hold.

MANHATTAN
GMAT

Chapters

Structure-Based Family

Renaissance Masters

Many people praise High Renaissance painting for creating very realistic images
from observation, but scholars have documented that some High Renaissance
painters used pinhole cameras to project the likeness of their subjects onto
the canvas and painted from there. Thus, people who credit High Renaissance
painters with superior artistic skills are misguided. Painting from a projected
image requires only an insignificant amount of additional skill beyond that
needed to copy a picture outright.

In the argument given, the two boldfaced portions play which of the following
roles?

(A) The first is a finding that has been used to support a conclusion that the
argument rejects; the second is a claim that supports that conclusion.

(B) The first is a finding that has been used to support a conclusion that the
argument rejects; the second is that conclusion.

(C) The first is a claim put forth to support a conclusion that the argument re-
jects; the second is a consideration that is introduced to counter the force of
that evidence.

(D) The first is evidence that forms the basis for the position that the argument
seeks to establish; the second is a claim presented to solidify that position.

(E) The first is evidence that forms the basis for the position that the argument
seeks to establish; the second is that position.

Democracy

As the United States demonstrated during its early development, it is not enough
for citizens simply to have rights; the successful functioning of a democracy
requires that they also know how to exercise those rights. Access to formal educa-
tion was one necessary component that helped the U.S. citizenry to learn how to
exercise its rights. Therefore, in order for a democracy to function successfully, its
citizens must have access to a formal education.

The author develops the argument by

(A) using an analogy to establish a precedent for a planned future event

(B) illustrating differences in the requirements for the functioning of a
democracy depending upon the democracy in question

(D) forming a hypothesis that explains apparently contradictory pieces of
evidence

(E) supplying an alternate explanation for a known phenomenon

ATTAN

GMAT

Structure-Based Family

Chapter 3

4. Malaria

In an attempt to explain the cause of malaria, a deadly infectious disease, early
European settlers in Hong Kong attributed the malady to poisonous gases sup-
posedly emanating from low-lying swampland. In the 1880s, however, doctors
determined that Anopheles mosquitoes were responsible for transmitting the
disease to humans after observing that the female of the species can carry a
parasitic protozoan that is passed on to unsuspecting humans when a mos-
quito feasts on a person's blood.

What function does the statement in boldface fulfill with respect to the argument
presented above?

(A) It provides support for the explanation of a particular phenomenon.

(B) It presents evidence that contradicts an established fact.

(D) It identifies the cause of an erroneous conclusion.

(E) It proposes a new conclusion in place of an earlier conjecture.

5. Digital Marketing

Sania: The newest workers in the workforce are the most effective digital market-
ing employees because they are more likely to use social networking websites
and tools themselves.

Carlos: But effective digital marketing also requires very technical expertise, such
as search engine optimization, that is best learned on the job via prolonged expo-
sure and instruction.

Carlos responds to Sania by

(A) demonstrating that Sania's conclusion is based upon evidence that is not
relevant to the given situation

(B) questioning the accuracy of the evidence presented by Sania in support of
her conclusion

(D) pointing out differences in the qualifications desired by different employers
seeking digital marketing employees

(E) providing an additional piece of evidence that undermines a portion of
Sania's claim

MANHATTAN
GMAT

Chapter 3 Structure-Based Family

6. Innovative Design

Products with innovative and appealing designs relative to competing products
can often command substantially higher prices in the marketplace. Because
design innovations are quickly copied by other manufacturers, many con-
sumer technology companies charge as much as possible for their new designs
to extract as much value as possible from them. But large profits generated by
the innovative designs give competitors stronger incentives to copy the designs.
Therefore, the best strategy to maximize overall profit from an innovative
new design is to charge less than the greatest possible price.

In the argument above, the two portions in boldface play which of the following
roles?

(A) The first is an assumption that supports a described course of action; the
second provides a consideration to support a preferred course of action.

(B) The first is a consideration that helps explain the appeal of a certain strategy;
the second presents an alternative strategy endorsed by the argument.

(D) The first is a consideration that demonstrates why a particular approach is
flawed; the second describes a way to amend that approach.

(E) The first is a factor used to rationalize a particular strategy; the second is a fac-
tor against that strategy.

MANHATTAN
GMAT

Structure-Based Family

7. Gray Wolf Population

Government representative: Between 1996 and 2005, the gray wolf popula-
tion in Minnesota grew nearly 50 percent; the gray wolf population in Montana
increased by only 13 percent during the same period. Clearly, the Minnesota gray
wolf population is more likely to survive and thrive long term.

Environmentalist: But the gray wolf population in Montana is nearly 8 times the
population in Minnesota; above a certain critical breeding number, the popula-
tion is stable and does not require growth in order to survive.

The environmentalist challenges the government representative's argument by
doing which of the following?

(A) introducing additional evidence that undermines an assumption made by
the representative

(B) challenging the representative's definition of a critical breeding number

(D) implying that the two populations of wolves could be combined in order to
preserve the species

(E) suggesting that the Montana wolf population grew at a faster rate than
stated in the representative's argument

Structure-Based Family

Solutions

1. Ad Revenues: The correct answer is B.

Step 1: Identify the question.

The portions in boldface play
which of the following roles in
i the media critics argument?

Step 2: Deconstruct the argument.

Media Critic: Network ex-
ecutives allege that television
viewership is decreasing due
to the availability of television
programs on other platforms,
such as the internet and mobile
devices.

These executives claim that de-
clining viewership will cause
advertising revenue to fall and
networks will thus be unable
to spend the large sums neces-
sary to produce high-quality
programming.

That development, in turn, will
lead to a dearth of programming
for the very devices that canni-
balized televisions audience.

However, research shows that
users of alternative platforms are
exposed to new programs and,
as a result, actually increase the
number of hours per week that
they watch television.

R A B C D E

MC: NE say TV I b/c use
other Ps

R A B C D E

MC: NE say TV 4 b/c use
other Ps

NE: TV I -» ad I -» no $
for qual prog

R A B C D E

MC: NE say TV I b/c use
other Ps

NE: TV I -* ad I -» no $
for qual prog no prog for
other Ps

R A B C D E

MC: NE say TV I b/c use
other Ps

NE: TV I -» ad I -» no $
for qual prog no prog for
other Ps

This is a Role question. The ques-
tion contains the word "boldface,"
and I'm asked to find the "role" of
each bold statement.

The word "allege" tells me this is
a claim. Also, the critic is talking
about what other people claim, so
Vm guessing the critic is going to
contradict what they claim — so
this is probably a counterpremise.

More from the NEs. More claims
about bad things happening. Is
the last thing the NEs conclusion?
This is the 1st boldface. If the MC
does contradict the NEs later,
then this first boldface will be
labeled an X.

Ah, I see. Ironic. The fact that
people are watching on other plat-
forms will eventually lead to not
having enough programming for
those other platforms. Conclusion
of the NEs.

Here's the contradiction! Til wait
till I find the conclusion for sure,
but the first boldface is probably
anX.

BUT alt P users watch
MORE TV

Chapter 3

Structure-Based Family

This demonstrates that alterna-
tive platforms will not prevent
networks from increasing adver-
tising revenue.

A B C D E

MC:NEsayTV4b/cuse
other Ps

©NE: TV 4- -* ad I -» no $
for qual prog -» no prog for
other Ps

©BUT alt P users watch
MORE TV

©ad rates

I want this combo: X P

Hmm. I didn't think of that. The
recyclable materials still have to
go somewhere. Okay, the MC is
concluding the opposite: that ad
rates will go up. And if that's my
conclusion, then the first boldface
is indeed an Xand the second one
supports the conclusion, so it's a P.

Step 3: State the Goal.

The question asks me to find the role of two boldface statements. The MC's conclusion is in the last line, and
the second boldface, right before it, supports that conclusion. The second boldface is a P. The first boldface is
part of the NE's argument, which is the opposite of the MC's argument, so the first boldface is an X. I want to
find the combo XP (in that order) in an answer choice.

Step 4: Work from wrong to rig ht.

(A) The first is an inevi-
table trend that weighs
against the critic's claim;
the second is that claim.

A B C D E

MC: NE say TV 4 b/c use
other Ps

©NE: TV I -> ad I -» no $
for qual prog -» no prog for
other Ps

©BUT altP users watch
MORE TV

©ad rates

I want this combo: X P

"Weighs against the MC's claim" — yes,
that's consistent with an X label. The
second is "that" claim, meaning the MC's
claim. No. the second one is a P, not a C

(Note: the word " inevitable" can also be
considered incorrect. The trend described in
the first statement says that ad rates will go
down, but the MC provides a reason why
ad rates wouldn't go down. . . so the trend
j isn't necessarily inevitable.)

GMAT

Structure-Based Family

Chapter 3

MC:NEsayTV4< b/cuse
other Ps

(B) The first is a predic- S R ABCDE
tion that is challenged
by the argument; the
second is a finding upon
which the argument ©NE: TV I - ad I -+ no $

depends. for <l ual P ro g ~* no P ro S for

other Ps

©BUT alt P users watch
MORE TV

©ad rates

I want this combo: X P
R A B € D E

(D) The first acknowl-
edges a position that the
network executives ac-
cept as true; the second
is a consequence of that
position.

MC: NE say TV I b/c use
other Ps

©NE: TV I -» ad I -> no $
for qual prog no prog for
other Ps

©BUT altP users watch
MORE TV

©ad rates

I want this combo: X P
R A B € B E

j MC: NE say TV I b/c use
other Ps

©NE: TV I -> ad I -> no $
for qual prog -» no prog for
other Ps

©BUT altP users watch
| MORE TV

I ©ad rates

I want this combo: X P

That's true, the MC does challenge the first
one. That's an X. And the second one is
a P, so we can describe that as something
upon which the MC's argument depends.
Keep this one in.

Clarifies the MCs claim? No. The first one
is something the NE's claim. I dont even
need to read the second half of the answer.

j Yes, the NEs do accept the first boldface as
true — it's their premise. And they're on

j the opposite side of the MC, so something
they think isanX. Okay, that's fine. "The
second is a consequence of that position. "
What position? Oh, they use "position" in

j the first half of the sentence. . . the NE's
position. The second isn't something about
the NE's position. It goes against the NE's
position. No.

MANHATTAN 75
GMAT

Chapter 3

Structure-Based Family

(E) The first op-
poses the critic s claim
through an analogy;
the second outlines a
scenario in which that
claim will not hold.

R A(B)€ B E

MC: NE say TV I b/c use
other Ps

©NE: TV I -> ad 1 -» no $
for qual prog -» no prog for
other Ps

(P)BUT altP users watch
MORE TV

©ad rates

I want this combo: X P

| The first one does oppose what the MC con-
| eludes. I'm not quite sure whether it does
| so "through an analogy" Let's look at the
second half. A scenario in which theMC's
claim wont hold — meaning something
that's on the opposite side of what the MCs
say. No! The second one outlines a scenario
in which the NE's claim won't hold, not
I the MCs claim.

2. Renaissance Masters: The correct answer is D.

Step 1: Identify the question.

In the argument given, the two
boldfaced portions play which
of the following roles?

Step 2: Deconstruct the argument.

Many people praise High
Renaissance painting for creat-
ing very realistic images from
observation,

but scholars have documented
that some High Renaissance
painters used pinhole cameras
to project the likeness of their
subjects onto the canvas and
painted from there.
Thus, people who credit High
Renaissance painters with supe-
rior artistic skills are misguided.

A B C D E

R A B C D E

ppl like HR pntg b/c realstc

R A B C D E

ppl like HR pntg b/c realstc

BUT some HR pntrs just
project / trace

R A B C D E

ppl like HR pntg b/c realstc

BUT some HR pntrs just
project / trace

ppl who like HR =
misguided

The word " boldfaced," along with
the boldface font in the argument,
indicates that this is a Role ques-
tion.

j The "many people" intro feels like
there's a contrast coming. . . and
there is! Okay, let's just get this
j piece down first.
| Okay, so people think the HR
j painters can paint realistically just
\ by observing, but actually some
were just projecting the images
onto a canvas and sort of tracing
the image.

The word "thus" might mean
this is the conclusion. Hmm. The

previous sentence only said that
"some"HR painters did the trac-

j ing thing, not all of them. But this

j sentence seems to be condemning

j all of them.

GMAT

Structure-Based Family

Chapters

Painting from a projected image R A B C D E

requires only an insignificant
amount of additional skill
beyond that needed to copy a
picture outright.

n/a

ppl like HR pntg b/c realstc

BUT some HR pntrs just
project / trace

©ppl who like HR =
misguided

project / trace = 4 skill
R A B C D E

ppl like HR pntg b/c realstc

BUT some HR pntrs just
project / trace

©ppl who like HR =
misguided

project / trace = I skill

Step 3: State the Goal.

I need to identify the role of the two boldfaced statements as they relate to the conclusion — which was that
people who think HR painters are really skilled are misguided. The first one is a fact, and the second one is an
opinion. I'm going to try to fact I opinion strategy and see how that works.

Okay, the last sentence was
definitely the conclusion. This sen-
tence is supporting the conclusion.
If this is true, then yes, painters
who use this technique arent that
great.

Vm not 100% sure how to label
the first boldface, but I did notice
that the first one was a fact and
the second one was a claim. I
could use that alternate conclusion
I fact I opinion strategy.

Step 4: Work from wrong to right.

R A B C D E
ppl like HR pntg b/c realstc
BUT some HR pntrs just

(A) The first is a find-
ing that has been used
to support a conclu-
sion that the argument
rejects; the second is a project / trace

claim that supports that Q pp i w h G like HR =

misguided

project / trace = I skill

A " finding" could be a fact, and a claim is
an opinion, so this one is okay so far.

conclusion.

MANHATTAN
GMAT

er3

Structure-Based Family

(B) The first is a finding
that has been used to
support a conclusion
that the argument re-
jects; the second is that
conclusion.

R A8CDE

ppl like HR pntg b/c realstc

BUT some HR pntrs just
project / trace

©ppl who like HR =
misguided

project / trace = I skill

A "finding" could be a fact, but the conclu-
sion is the conclusion; it doesn't fit into the
"opinion" category. (Recall that an opinion
is any claim that is NOT the conclusion.)
This one's wrong.

(C) The first is a claim
put forth to support
a conclusion that the
argument rejects; the
second is a consideration
that is introduced to
counter the force of that
evidence.

R A B € D E

ppl like HR pntg b/c realstc

BUT some HR pntrs just
project / trace

©ppl who likeHRR-
misguided

project / trace = 1 skill

A "claim" is not a fact. I can eliminate this
one.

(D) The first is evidence
that forms the basis
for the position that
the argument seeks to
establish; the second
is a claim presented to
solidify that position.

R A B € D E

ppl like HR pntg b/c realstc

BUT some HR pntrs just
project / trace

©ppl who likeHRR =
misguided

project / trace = I skill

"Evidence" can be a fact, and a claim is a
claim. This one has to stay in, too.

(E) The first is evidence
that forms the basis for
the position that the
argument seeks to estab-
lish; the second is that
position.

R A B € D E

ppl like HR pntg b/c realstc

BUT some HR pntrs just
project / trace

©ppl who like HR =
misguided

project / trace = I skill

"Evidence" can be a fact, but the second
boldface is a claim, while this choice says
that the second boldface is the "position, " or
conclusion. I can eliminate this one.

MANHATTAN

GMAT

Structure-Based Family

Chapt

compare A and D

R A fi €©E

ppl like h-R pntg b/c realstc

BUT some h-R pntrs just
project / trace

@ppl who like h-R =
misguided

project / trace = I skill

3. Democracy: The correct answer is C.
Step 1: Identify the question.

The author develops the argu- DA
ment by

A B C D E

Step 2: Deconstruct the argument.

As the United States demon-
strated during its early devel-
opment, it is not enough for
citizens simply to have rights;
the successful functioning of a
democracy requires that they
also know how to exercise those
rights.

Access to formal education was
one necessary component that
helped the US citizenry to learn
how to exercise its rights.

A B C D E

Based on the fact I opinion guessing tech-
nique, I cant get any further; I just have to
guess between B andD. Using the regular
technique, both boldfaces are Premises used
to support the authors conclusion. Answer
A says that the first boldface is used "to
support a conclusion that the argument
rejects. "Eliminate answer A.

Ex: US Cit have rights and exer-
cise rights success democ

A B C D E

Ex: formal edu -» US Cit have
rights and exercise rights -» suc-
cess democ

The wording is similar to a
Describe the Argument question,
though it doesnt have the "two
people talking" feature. This
might be one of the rare variants
that doesnt have two people talk-
ing. A quick glance at the abstract
wording of the answer choices
confirms: this is a Describe Arg
question.

Okay, specific example of a prin-
ciple: the US showed that citizens
need to have rights AND know
how to exercise those rights.

More detail on the US example.
Formal education was needed to
know how to exercise those rights.

MANHATTAN
GMAT

Chapters

Structure-Based Family

Therefore, in order for a democ-
racy to function successfully, its
citizens must have access to a
formal education.

DA A B C D E Conclusion. The author s just sort

Ex: formal edu -> US Cit of putting together the two "end"

i . r j . , I pieces of the argument here.

nave rights and exercise rights r J *

success democ

©formal edu nec for success
democ

Step 3: State the Goal.

The author concludes that formal education is necessary in general for a democracy to be successful. The evi-
dence: it happened this way in one country (the US).

Step 4: Work from wrong to rig ht.

(A) using an analogy to
establish a precedent for
a planned future event

(B) illustrating differ-
ences in the require-
ments for the function-
ing of a democracy
depending upon the
democracy in question

(D) forming a hy-
pothesis that explains
apparently contradictory
pieces of evidence

DA A B C D E

Ex: formal edu US Cit
have rights and exercise
rights -» success democ

©formal edu nec for success
democ

DA ABC D E

Ex: formal edu US Cit
have rights and exercise
rights success democ

©formal edu nec for success
democ

DA AfiCDE

Ex: formal edu ~* US Cit
have rights and exercise
rights -> success democ

©formal edu nec for success
democ

DA A B CBE

Ex: formal edu ~* US Cit
have rights and exercise
rights -» success democ

©formal edu nec for success
democ

The argument used an example. Is that they
same thing as an analogy? Maybe. Oh, but
what's the "planned future event"? There isn't
anything; rather, the author concluded with
a general statement, not a discussion of an
event.

I can imagine that it would be true that
there are different requirements for differ-
ent governments. . . but that's not what this
argument says. The author only mentions the
US and then concludes something in general
about that.

This looks decent. The argument did in-
troduce an example and then used that to
conclude a general principle.

It would be reasonable to describe the conclu-
sion as a hypothesis. . . but there aren't any
contradictory things in the argument. Rather,
the example given does illustrate the conclu-

sion.

GMAT

Structure-Based Family

(E) supplying an alter-
nate explanation for a
known phenomenon

| DA A B©B E

Ex: formal edu -* US Cit
j have rights and exercise
rights success democ

©formal edu nec for success
democ

The author doesrit supply an "alternate'
explanation; he isn't arguing against anyone.
He just concludes something from the US
example.

4. Malaria: The correct answer is A.

Step 1: Identify the question.

What function does the state-

R ABCDE

ment in boldface fulfill with

respect to the argument pre-

sented above?

Step 2: Deconstruct the argument.

In an attempt to explain the cause of
malaria, a deadly infectious disease,
early European settlers in Hong Kong ;
attributed the malady to poisonous
gases supposedly emanating from low- 1
lying swampland.
In the 1880s, however, doctors de-
termined that Anopheles mosquitoes
were responsible for transmitting the j
disease to humans after observing that j
the female of the species can carry
a parasitic protozoan that is passed
on to unsuspecting humans when a
mosquito feasts on a person's blood.

R ABCDE
ES: Pgas -* M

R ABCDE

ES: Pgas -» M

1880: mosq -» M by
blood

I want this combo: P

This is a Role question. The ques-
tion contains the word "boldface,"
and I'm asked to find the "func-
tion" of each bold statement.

This is a fact. Likely either back-
ground or premise.

Okay, this is still a fact, but it's
the conclusion of the story. They
used to think it was one thing,
and then they figured out it was
really the mosquitoes. The bold-
face language, in particular, is the
evidence used to show that it was
mosquitoes. That's a Premise.

(Note: our "combo" in this case consists of only one label because we only have one boldface statement.)
Step 3: State the Goal.

The question specifically asks me what role this information plays: "the female carries a PP that is passed to
humans when a mosquito <bites someone>. "Because of that, the scientists decided that the mosquitoes were
transmitting the disease. That's the most like a P — a premise that supports some further conclusion.

I need to find the abstract language that indicates some kind of premise or support.

Chapter 3

Structure-Based Family

Step 4: Work from wrong to right.

(A) It provides support
for the explanation of a
particular phenomenon.

(B) It presents evidence
that contradicts an
established fact.

(D) It identifies the
cause of an erroneous
conclusion.

(E) It proposes a new
conclusion in place of
an earlier conjecture.

R ABCDE

ES: Pgas -» M

1880: mosq -» M by blood

I want this combo: P
R ABCDE

ES: Pgas M

1880: mosq -> M by blood

I want this combo: P

R A66DE
ES: Pgas -» M
1880: mosq -» M by blood
I want this combo: P

R A8€BE

ES: Pgas -* M

1880: mosq -» M by blood

I want this combo: P
R <g)B € B E

ES: Pgas -* M

1880: mosq M by blood

I want this combo: P

"Support" — that's good — for a "phenom-
enon" Okay, that's just fancy-speak for:
provides support for something that hap-
pened. That sounds okay. Leave it in.

"Evidence" — that's also good. And that
evidence does "contradict" what the earlier
settlers thought! Oh, wait — was that an
established fact? Let me look at the first sen-
\ tence again. No, they thought that, but the
\ argument doesn't say it was an "established
fact. " Cross this one off
"Confirmation" is also good. . . of a "con-
\ tested assumption." I'm not quite sure what
they're referring to when they say "assump- \
\ Hon, " but nothing was contested here. First, I
I some people thought one thing, and later,
\ new evidence led some doctors to conclude
something else. No.

No — the only thing we might be able to
j describe as an erroneous conclusion is what
\ the early settlers thought. But the bold stuff

supports the doctors' conclusion.

Oh, yes, a new conclusion. Yes, that's ex-
actly what the argument says! Oh, wait — / I
labeled the boldface stuff a P, not a C. Why
was that? Oh, I see — tricky. The first half
of the sentence, the non-bold part, is the
new conclusion. The bold part is the evi-
dence supporting that. This isn't it after all!

GMAT

Structure-Based Family

5. Digital Marketing: The correct answer is E.
Step 1: Identify the question.

Carlos responds to Sania by

A B C D E

Step 2: Deconstruct the argument.

Sania: The newest workers in
the workforce are the most
effective digital marketing em-
ployees because they are more
likely to use social networking
websites and tools themselves.

A B C D E

S: new empl use soc nw
most eff dig mktg empl ©

The "two person" structure and
the focus on how Carlos responds
indicate that this is a Describe the
Argument question.

Sania claims that the workers who
use certain online tools are also
the most effective at digital mar-
keting, and that those people are
the newest workers. In order to
conclude that they re the MOST
effective, she must be assuming
that this is the most important
criterion by which to judge such
employees.

Carlos doesnt dispute Sania s
evidence, but he brings up a new
point: you also need these other
skills to be a good digital market-
er. . . and those skills are learned
on the job over a long time ("pro-
longed"). . . which hurts Sania's
claim that the newest workers are
the most effective.

Step 3: State the Goal.

/ need to articulate how Carlos responds to Sania. He doesnt say that she's wrong about the newest workers
using social networking tools. Rather, he says that digital marketers also need this other skill that takes a long
time to learn on the job. If that's the case, then this weakens Sania 's claim that the newest workers are the
most effective.

Carlos: But effective digital
marketing also requires very
technical expertise, such as
search engine optimization, that
is best learned on the job via
prolonged exposure and instruc-

A B C D E

S: new empl use soc nw ->
most eff dig mktg empl ©

C: SE opt learn on job over
long time eff dig mktg

tion.

Chapter 3

Structure-Based Family

Step 4: Work from wrong to rig ht.

(A) demonstrating that
Sania's conclusion is
based upon evidence
that is not relevant to
the given situation

(B) questioning the ac-
curacy of the evidence
presented by Sania in
support of her conclu-
sion

(D) pointing out differ-
ences in the qualifica-
tions desired by differ-
ent employers seeking
digital marketing
employees

(E) providing an addi-
tional piece of evidence
that undermines a por-
tion of Sania's claim

A B C D E

S: new empl use soc nw ~>
most eff dig mktg empl ©

C: SE opt learn on job over
long time eff dig mktg
DA AfiCDE

S: new empl use soc nw -»
most eff dig mktg empl ©

C: SE opt learn on job over
long time eff dig mktg
DA ABGDE

S: new empl use soc nw
most eff dig mktg empl©

C: SE opt learn on job over
long time ~* eff dig mktg
DA A B € B E

S: new empl use soc nw
most eff dig mktg empl ©

C: SE opt learn on job over
long time eff dig mktg

DA A B € B(E)

S: new empl use soc nw -»
most eff dig mktg empl ©

C: SE opt learn on job over
long time -» eff dig mktg

6. Innovative Design: The correct answer is C.
Step 1; Identify the question.

In the argument above, the two
portions in boldface play which
of the following roles?

Carlos doesn't say anything negative about
Sania's evidence; rather, he introduces new
evidence that attacks Sania's assumption
that her piece of evidence is the most impor-
tant thing to consider.

Carlos doesn't attack Sania's evidence;
rather, he introduces new evidence that
attacks Sania's assumption that her piece
of evidence is the most important thing to
consider.

Carlos does contribute an additional piece
of evidence, but his new evidence hurts
Sania's argument. Carlos doesn't support
Sania's conclusion.

Carlos does point out a different way to
assess the effectiveness of digital marketing
employees, but he doesn't mention employ-
ers at all or differences among different
employers.

Bingo. This is exactly what Carlos does — a
new piece of information that hurts the
"newest workers" portion of Sania's claim.

A B C D E

; This is a Role question. The ques-
\ Hon contains the word "boldface," \
j and I'm asked to find the "role" of
\ each bold statement.

GMAT

Structure-Based Family

Step 2: Deconstruct the argument.

Products with innovative and
appealing designs relative to
competing products can often
command substantially higher
prices in the marketplace.
Because design innovations
are quickly copied by other
manufacturers, many consum-
er technology companies charge
as much as possible for their
new designs to extract as much
value as possible from them.
But large profits generated by
the innovative designs give
competitors stronger incentives
to copy the designs.

Therefore, the best strategy to
maximize overall profit from
an innovative new design is to
charge less than the greatest
possible price.

R A B C D E
ID -» tt $

R A B C D E
ID ^ Tt $

others copy, so COs charge
Tt $

R A B C D E
ID -» TT $

others copy, so COs charge
TT $

BUT TT prof -» faster copy
R A B C D E

ID -» TT $

others copy, so COs charge
TT $

BUT TT prof -» faster copy

)to max prof, charge < than
max price

I want this combo: P C

Sort of between a fact and a
claim. Probably a premise.

Getting more towards claim-based
material, but I'm not sure this is
the conclusion.

BUT signals a contrast. Oh, so
there s actually a drawback to
making a lot of money: competi-
tors will copy even faster so I guess
that could hurt market share.
That's interesting.

Here we go, the conclusion. The
person s claiming that companies
actually shouldn't charge the
largest possible price and this will
actually help maximize profits in
the end. The second boldface is the
conclusion; that gets a C. And the
first is a Premise that supports this
conclusion.

Step 3: State the Goal.

The question asks me to determine the role played by each of 2 boldface statements. I've decided the second
one is the conclusion and the first is a premise supporting that conclusion, so I want to find an answer that
gives this combo: P C (premise, then conclusion).

Chapters

Structure-Based Family

Step 4: Work from wrong to right.

(A) The first is an
assumption that sup-
ports a described course
of action; the second
provides a consideration
to support a preferred
course of action.

(B) The first is a con-
sideration that helps
explain the appeal of a
certain strategy; the sec-
ond presents an alterna-
tive strategy endorsed by
the argument.

(D) The first is a consid-
eration that demon-
strates why a particular
approach is flawed; the
second describes a way
to amend that approach.

R A B C D E
ID-> tt$

others copy, so COs charge
tt $

BUT tt prof -» faster copy

)to max prof, charge < than
max price

I want this combo: P C
R A B C D E

ID ^ tt $

others copy, so COs charge
tt $

BUT tt prof -* faster copy

)to max prof, charge < than
max price

I want this combo: P C
R ABC D E

ID tt $

others copy, so COs charge
tt $

BUT tt prof -» faster copy

)to max prof, charge < than
max price

I want this combo: P C
R A B C B E

ID tt $

others copy, so COs charge
tt $

BUT tt prof -> faster copy

)to max prof, charge < than
max price

I want this combo: P C

Hmm, they call the first an assumption, not
a premise, but I suppose that's okay; they
do say it "supports" something. The second,
though, is the actual conclusion — but this
answer choice makes the second sound like
another premise. Idont think so.

The wording for the first statement is a
little strange, but I suppose that could be
considered a premise. Okay. The word-
ing for the second definitely doesnt work,
though — the second isn't discussing an
"alternative" strategy compared to the first.
The first one actually supports the second!

Something that " justifies" something else. . .
yes, this could be a way to describe some-
thing that supports something else. That
part's okay. And the second part "is that
strategy" — yes, strategy could be a synonym
for conclusion. Keep this one in.

No, the first supports the conclusion — it
doesnt illustrate a flaw. I don't even need
to read the second half of this choice.

GMAT

Structure-Based Family

(E) The first is a factor
used to rationalize a
particular strategy; the
second is a factor against j
that strategy. j

R AB©BE
ID -» tt $

others copy, so COs charge
tt $

BUT 1 1 prof -» faster copy

©to max prof, charge < than
max price

I want this combo: P C

Something used to "rationalize" a "strate-
gy"? Yes, that could be describing a premise
that supports a conclusion. Oh, but the
second goes against the strategy? No! The
second is actually the strategy, or conclu-
sion.

7. Gray Wolf Population: The correct answer is A.
Step 1: Identify the question.

The environmentalist challenges
the government representatives
argument by doing which of the
following ?

DA A B C D E

Step 2: Deconstruct the argument.

Government representative: Be- \
tween 1996 and 2005, the gray j
wolf population in Minnesota
grew nearly 50 percent; the gray l
wolf population in Montana
increased by only 13 percent
during the same period.
Clearly, the Minnesota gray
wolf population is more likely to \
survive and thrive long term.

A B C D E

GR: 96-05, Min GW t
50%, Mon GW t 13%

A B C D E

GR: 96-05, Min GW t
! 50%, Mon GW t 13%

©Min > likely to survive/thrive

We have a 2~person-talking struc-
ture, and we're asked how the
second person responds; this is a
Describe the Argument question.

This is just a straight fact. The
Minnesota wolf population grew a
lot faster in that time period than
the Montana wolf population.

Conclusion! Claiming that Min-
nesota wolves are more likely to
survive and thrive. Certainly, the
Minnesota wolf population grew
more. . . but does that automati-
cally mean they re more likely to
survive and thrive?

Structure-Based Family

GR: 96-05, Min GW T
50%, Mon GW t 13%

DA A B C D E Ah, okay. The environmentalist

is pointing out that they're not

I necessarily the same thing. Once

\ the population is large enough,
©Min > likely to survive/thrive \ it > s a i ready stMej so isn > t

E: BUT Mon 8x Min; when I necessarily critical to survival.
t enough, already stable

Environmentalist: But the gray
wolf population in Montana is
nearly 8 times the population
in Minnesota; above a certain
critical breeding number, the
population is stable and does
not require growth in order to
survive.

Step 3: State the Goal

The GR concludes that the Min wolves are more likely to survive and thrive because the growth rate was a lot
higher, but the E responded that the Mon population was already a lot larger, so growth might not have been
necessary to keep the population thriving. The Mon population might already have been stable in the first
place.

I need to find something that explains this is a more abstract way: a new piece of evidence changes the way we
think about the issue addressed in the conclusion (surviving and thriving).

Step 4: Work from wrong to right.

(A) introducing ad-
ditional evidence that
undermines an as-
sumption made by the
representative

A B C D E

(B) challenging the rep-
resentative s definition
of a critical breeding
number

GR: 96-05, Min GW T
50%, Mon GW T 13%

©Min > likely to survive/
thrive

E: BUT Mon 8x Min;
when t enough, already
stable

DA AfiCDE

GR: 96-05, Min GW t
50%, Mon GW T 13%

©Min > likely to survive/
thrive

E: BUT Mon 8x Min;
when t enough, already
stable

This sounds pretty good. The Es statement is
a new piece of evidence, and it does under-
mine the Rs assumption that growth is a good
indicator of likelihood to survive and thrive.

The E does challenge the Rs assumption
about what it takes to survive and thrive, but
the E can't challenge the R on "critical breed-
ing number, " because the R never mentions
this concept.

Structure-Based Family

Chapter 3

A B € D E

(D) implying that
the two populations
of wolves could be
combined in order to
preserve the species

(E) suggesting that the
Montana wolf popula-
tion grew at a faster rate
than stated in the repre-
sentative s argument

GR: 96-05, Min GW T
50%, Mon GW t 13%

©Min > likely to survive/
thrive

E: BUT Mon 8x Min;
when T enough, already
stable

DA A B € B E

GR: 96-05, Min GW t
50%, Mon GW t 13%

])Min > likely to survive/
thrive

E: BUT Mon 8x Min;
when t enough, already
stable

DA ®B € & E

GR: 96-05, Min GW t
50%, Mon GW t 13%

^)Min > likely to survive/
thrive

E: BUT Mon 8x Min;
when t enough, already
stable

The E does mention the concept of "critical
breeding number" but establishes only that
the number of wolves in each population
differs significantly, not that the number of
wolves needed to achieve the "critical breed-
ing number' is different.

This might be an interesting strategy, but the
E doesnt actually mention it.

This is tricky if we're not reading very care-
fully. The E does introduce a new figure,
but that figure has to do with the size of the
two populations, not the rate of growth. The
E does not dispute the R's figures for rate of
growth.

GMAT

Chapter/ 4

Critical Reasoning

Assumptions

Assumption Family Questions
Find the Assumption (FA) Questions
Evaluate the Argument Questions

Flaw Questions

Assumptions

We briefly introduced assumptions in chapter 2, but we haven't done much yet with this concept. As-
sumptions are the key to the largest family of questions, the Assumption Family; all questions in this
family require us to identify and conduct some reasoning using some assumption made by the author.
(When we refer to the "author," were referring to a hypothetical person who is "speaking" the argument
and believes the argument to be valid. Were not referring to the test writer.)

An assumption is something that the author must believe to be true in order to draw a certain conclusion;
however, the author does not state the assumption in the argument. The assumption itself might not nec-
essarily be true in the real world; the only requirement is that the author has to believe its true in order
to make his or her claim.

For example, what is the author of the below argument assuming must be true?

Amy got an A on the test. Therefore, Amy must have studied for a long time.

therefore

Amy got an A |. Amy must have studied

on the test. I ^ for a long time.

(premise) (conclusion)

The author assumes that, in order to get an A on the test, it is absolutely required to study for a long
time. Note that the author is not just assuming that studying for a long time is one way to get an A on
the test. The author concludes that Amy must have studied for a long time, so that is the only way.

The diagram above represents the core of the argument; we previously discussed the core in Chapter 1.
The core consists of the conclusion and the main premise or premises that lead to that conclusion, as
well as the assumption.

Chapter 4

Assumptions

Assumptions fill a gap in the argument; the gap is represented by the arrow in the diagram above. If we
insert a correct assumption into the argument, it makes the argument stronger:

Amy got an A on the test. Studying for a long time is the only way to get an A. Therefore,
Amy must have studied for a long time.

Amy got an A
on the test.

(premise)

therefore

Studying for a long
time is the only way
to get an A

Amy must have studied
for a long time.

(conclusion)

(assumption)

Most GMAT arguments will contain multiple assumptions. Any one assumption will not automatically
make the argument air-tight, but it will make the conclusion more likely to be true. Brainstorm some
assumptions for this argument:

Thomas's football team lost in the championship game last year. The same two
teams are playing in the championship game again this year, and the players on
Thomas's team have improved. Therefore, Thomas's team will win the champion-
ship game this year.

The author is making multiple assumptions here. Thomas's team has improved enough to be better
than last year s winner. Last years winning team has not also improved enough to keep them ahead of
Thomas's team.

This brings us to a couple of important strategies for dealing with assumptions on the test.

Don't

do brainstorm assumptions you
can think of relatively easily

but

don't spend more than about 20
seconds brainstorming up front

do look for your brainstormed
assumptions in the answers

but

don't eliminate answers because
they don't match any of your
brainstormed assumptions

do find something that the
author must believe to be true in
order to draw the conclusion

but

don't hold out for something that
makes the conclusion "perfect" or
definitely true

MANHATTAN
GMAT

Assumptions

Chapter 4

Let s insert an assumption into our football argument and see how it works:

Thomas's football team lost in the championship game last year. The same two
teams are playing in the championship game again this year, and the players on
Thomas's team have improved enough to be better than the players on the defend-
ing champion team. Therefore, Thomas's team will win the championship game
this year.

That assumption does make the argument stronger, but we could easily argue that Thomas's team still
might not win. There are too many other potential factors involved; the author is making many as-
sumptions, not just one, in order to draw this conclusion.

Let's try another. On your scrap paper, draw out the core for the following argument, then try to brain-
storm some assumptions.

Charles is a sculptor. Therefore, he does not work in a practical field.

The first sentence offers a fact; the second offers a conclusion. Those are the two halves of our core, but
what is the gap in between?

Charles is a sculptor.

He does not work
in a practical field.

therefore

Sculpting is not practical.
Sculpting is not just a hobby

done in his spare time.
He does not hold a different
job in a practical field.

The author is making a number of assumptions here; three are shown in the diagram above. Differ-
ent people will brainstorm different assumptions; any are valid assumptions as long as the author must
believe them to be true in order to draw that conclusion.

GMAT

Chapter 4 Assumptions
Drill: Brainstorm Assumptions

i l llll I

Draw out the "core," and brainstorm at least one assumption that must be true in order to draw each
conclusion.

1 . Chocolate is Prabha's favorite flavor of ice cream. Therefore, she also likes chocolate
candy bars.

2. The employees of Quick Corp's accounting department consistently show a sig-
nificant jump in productivity in the two weeks before taking vacation. Clearly, the
knowledge that they are about to go on vacation motivates the employees to maxi-
mize their productivity.

3. Mayor: The Acme Factory has developed a new manufacturing process that uses
chemical Q, the residue of which is toxic to babies. In order to protect our children,
we need to pass a law banning the use of this chemical.

Answer Key for Drill: Brainstorm Assumptions

The assumption is noted in italics below the arrow. You may brainstorm different assumptions from the
one shown. Other assumptions are acceptable as long as they represent something that MUST be true
in order to draw the given conclusion.

The author assumes that Prabha will definitely like chocolate in at least one other form (candy bars).
The author assumes that its not true that she likes chocolate only in the form of ice cream.

therefore

Choc fav flav

ice cream

also likes
choc candy

She likes choc in other
forms than ice cream

MANHATTAN
GMAT

Assumptions

Chapter 4

2 wks b4 vaca:
I prod

emp choose to max
prod b4 vaca

therefore

. ^>

jump" is the same thing
as "max prod"
They didn't plan vacation to
occur right after a big dead-
line or other busy time.

The author assumes a couple of things here. First, the premise mentions only a "significant jump" in
productivity; it does not say that this productivity represents the employees' maximum productivity. So
the author is assuming that this significant jump does, in fact, represent the maximum productivity.

Second, the author concludes that employees decide to be more productive because they'll be taking
vacation soon. Perhaps its the case, instead, that the employees choose to take vacation right after they
know they'll be forced to work harder for some other reason. This author is assuming that this is NOT
the case — that employees are NOT choosing to take vacation after what they know will be a busy time
at work.

Acme using Q,
toxic baby

therefore

to protect kids,
banQ

If Acme uses Q, then kids will
somehow come into contact
with Q

The author assumes that use of chemical Q in the production process will somehow eventually expose
babies to the chemical residue. Maybe it's the case that the chemical is used only for something that
never comes into contact with the final product and will never come into contact with kids.

GMAT

Chapter 4 Assumptions

Assumption Family Questions

As we discussed earlier, there are 5 different types of assumption questions. We'll cover three, Find the
Assumption, Evaluate, and Flaw, in this chapter. In the next chapter, we'll learn about Strengthen and
Weaken questions. (Note: Find the Assumption Questions are one type of question in the overall As-
sumption Family.)

Each type of question has its own key characteristics and goals, but there are some commonalities across
all five types. There will be a conclusion, so we need to make sure to find it. In addition, while we read,
we also try to brainstorm any gaps, or assumptions, that we can in a short amount of time (but we don't
take very much longer than we take to read the argument itself).

Find the Assumption (FA) Questions

Find the Assumption questions ask us to find an assumption that the author must believe to be true in
order to draw the conclusion. The correct answer should make the argument stronger. In addition, if
the correct answer were not necessarily true, that would significantly harm the argument.

Our task is to figure out which answer choice represents something that must hold true according to
the author. Note one especially tricky aspect of these problems: the assumption itself might be flawed.
We might think, "Well, is that really true in the real world? I don't think that's necessarily true." Don't
ask that question! The only issue is whether the author must believe it to be true in order to arrive at his
or her conclusion. In our chocolate ice cream example from the last problem set, the author had to be-
lieve that Prabha liked at least one other form of chocolate (other than ice cream), but that assumption
could be false. Perhaps Prabha really does like chocolate only in the form of ice cream.

Identifying the Question

Most of the time, these questions are easy to identify because the question stem will use some form of
the noun "assumption" or the verb "to assume." Occasionally, the question will be worded differently.
It may ask for a new premise, or piece of information, that is "required" or a new premise that will help
the conclusion to be "more properly drawn" (or similar language). Here are a couple of examples:

Which of the following is an assumption on which the argument depends?

The conclusion above would be more properly drawn if it were established that

Let's look at a sample argument:

When news periodicals begin forecasting a recession, people tend to spend less
money on non-essential purchases. Therefore, the perceived threat of a future re-
cession decreases the willingness of people to purchase products that they regard
as optional or luxury goods.

MANHATTAN
GMAT

Assumptions

Chapter 4

Which of the following is an assumption on which the argument depends?
We'll look at the answers in a moment. Lets do our first couple of steps:

Step 1 ; Identify the question,

FA A B C D E

Which of the following is an
assumption on which the argu-
ment depends?

Step 2: Deconstruct the argument.

When news periodicals begin
forecasting a recession, people
tend to spend less money on
non-essential purchases.
Therefore, the perceived threat
of a future recession decreases
the willingness of people to pur-
chase products that they regard
as optional or luxury goods.

A B C D E

news Ps fore rec -> ppl spend
1$

A B C D E

news Ps fore rec -» ppl spend
1$

n/a

@prcvd fut thrt ppl spend I
$lux

FA A B C D E

news Ps fore rec -» ppl spend
4 $

©prcvd fut thrt ppl spend I
$lux

The question stem uses the word
"assumption" so it is the Assump-
tion type. Write "FA" on the scrap
paper and then the 5 answer
choice letters.

This sounds like a premise, though
I suppose it could be a conclusion.
The news Ps predict a recession,
and then people spend less money.
This is the conclusion. The
premise just tells us what people
do — spend less money. The con-
clusion tries to claim why they do
it — a perceived future threat.

What is the author assuming?
That people are actually read-
ing or hearing about the news P
forecasts. That the recession hasn't
already started and that's why
people are spending less money
— maybe the news Ps are just
slow in " forecasting" something
that has already started.

Did you come up with any other assumptions? The key is to get our brains thinking about these things,
but there are almost always multiple possible assumptions; we may not be able to brainstorm the exact
one that will show up in the answers.

MANHATTAN
GMAT

Chapter 4

Assumptions

Step 3; State the Goal.

My core is:

News Ps:

rec!

Prcvd threat spend $ I

I spend & 4

therefore

Ppl reading I hearing info

from News Ps
Threat only prcvd today;
hasn't actually started

I'll look for the assumptions I brainstormed, but I'll also be flexible; I might not have thought of the assump-
tion in the correct answer. On FA questions, traps often involve going too far out of scope (the answer is not
tied to the conclusion), using reverse logic (the answer makes the argument weaker, not stronger), or making
an irrelevant distinction or comparison. (Note: we'll discuss more about trap answers a bit later in the
chapter.)

Lets take a look at the full problem now.

Which of the following is an assumption on which the argument depends?

(A People do not always agree as to which goods should be considered luxury
goods.

(B) People are more likely to have read a news periodical recently because more
and more periodicals are being published.

(D) The consumer perception of the threat of recession increases when news
periodicals begin forecasting a recession.

(E) At least some of the biggest-spending consumers prior to the recession were
among those who curtailed their spending after the recession began.

100

MANHATTAN

GMAT

Assumptions

Step 4: Work from wrong to right

(A) People do not always
agree as to which goods
should be considered luxury
goods.

(B) People are more likely to
have read a news periodical
recently because more and
more periodicals are being
published.

A B C D E

news Ps fore rec ppl
spend I $

)prcvd fut thrt -> ppl
spend i> $ lux
FA A B C D E

news Ps fore rec ppl
spend I $

)prcvd fut thrt -> ppl
spend I $ lux

larly read news periodicals. n c _^ ,

J r news rs tore rec -» ppl

spend I $

©prcvd fut thrt ppl
spend l $ lux

(D) The consumer perception FA A B € D E

of the threat of recession in- ^ c _^ i

news Ps fore rec -> ppl

creases when news periodicals S p enc l l $
begin forecasting a recession.

©prcvd fut thrt ppl
spend A $ lux

A B €(D)E

(E) At least some of the
biggest-spending consumers
prior to the recession were
among those who curtailed
their spending after the reces- ©P^vd fut thrt -» ppl
sion began. s P end 1 $ lux

news Ps fore rec ~> ppl
spend I $

I can believe that this is true in the real
world, hut this is irrelevant to the con-
clusion. The argument is not based upon
whether people agree as to how to classify
certain goods.

This sounds a little bit like one of my
brainstormed assumptions — the argu-
ment is assuming that people are actually
reading those periodicals. I'm not so sure
about the "more periodicals are be-
ing published" part, though. You don t
absolutely have to believe that in order
to draw that conclusion. I'll keep it in
for now, but maybe I'll find something
better.

This is also about reading the peri-
odicals. . . but it's the opposite of what
I want! The argument needs to assume
that people DO read the Ps; if they don't,
then how can they be influenced by what
the Ps forecast!

let's see. News Ps begin forecasting, then
perception of threat increases, then people
spend less $. If that's true, then it IS
the case that the perception of the threat
leads people to spend less $. This one is
looking better than B. I can cross offB
now.

Hmm. This one sounds good, too. Maybe
if the biggest spenders keep spending
during the recession, then the overall
amount of money being spent won't go
down that much. . . although the argu-
ment doesn't really seem to depend on
how much it goes down. Oh, and this
says "after the recession began" — that
doesn't make sense with this conclusion.
The conclusion is about a "perceived
threat of a future recession. " Nice trap!

Chapter 4

Assumptions

We had a couple of good brainstormed assumptions ahead of time, but it turns out that we didn't brain-
storm the assumption contained in the correct answer, D. We did, however, see an "opposite" answer in
choice C; it contained information that was the opposite of one of our brainstormed assumptions, and
that made it easier for us to know that C was wrong.

The Negation Technique

On harder questions, we might find ourselves stuck between two answer choices. What can we do to
distinguish between tempting wrong answers and the right answer? We can try the Negation technique.

On Find the Assumption questions, the correct answer will be something that the author must believe
to be true in order to draw his or her conclusion. Because that is the case, if we were to negate the cor-
rect answer — say that it isn't true — then the authors argument should be harmed. Negating the cor-
rect answer should actually weaken the author's conclusion.

The Negation technique takes a bit of time to implement, so we don't want to use it on all five answer
choices, but the extra time needed might be worth it when we're stuck between two answers.

How do we do this? Let's try it out on the News Periodicals problem we just finished. Let's say that we
narrowed our answers to B and D:

(B) People are more likely to have read a news periodical recently because more
and more periodicals are being published.

(D) The consumer perception of the threat of recession increases when news
periodicals begin forecasting a recession.

Recall the argument itself:

news Ps fore rec ppl spend l $

@ prcvd fut thrt -> ppl spend I $ lux

That is, the author claims that the news Ps forecast a recession, which causes people to perceive a future
threat, and so people choose to spend less money on luxury goods.

What if answer choice B were NOT true? It would say something like:

(B) People are NOT more likely to have read a news periodical recently

(and) more periodicals are NOT being published.

Does this tear down the author's conclusion? Not really. The number of periodicals being published is
irrelevant to the argument.

Try negating answer D:

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Chapter 4

(D) The consumer perception of the threat of recession DOES NOT increase
when news periodicals begin forecasting a recession.

Hmm. If the news Ps forecast a recession, but the consumers don't actually perceive any threat of reces-
sion. . . then how can the author claim that they change their buying behavior based on perceiving this
threat? Negating this answer does weaken the author's conclusion, so this one is the right answer.

Don't use this technique on every answer choice, or you'll be in danger of spending too much time on
CR questions — but, when you're stuck, try to unstick yourself using the Negation technique.

Common Trap Answers

Let's take a look at some of the trap answers we saw in that last question and discuss the kinds of traps
that they typically try to set for us on Assumption questions.

On many FA questions, a trap answer will go too far out of scope: it won't actually address the conclu-
sion. Answer A in the above problem is a good example. The issue is not whether different people would
agree to classify the same item as a luxury good. Rather, the conclusion is about what causes someone to
spend less money on anything that that individual believes to be a luxury good.

Trap answers can also use reverse logic, which we see in answer choice C. Reverse logic does the op-
posite of what we want to do: in this case, answer C actually makes the argument worse, when we're
trying to articulate an assumption that would make the argument a bit stronger.

Answer E is an example of another trap: making an irrelevant distinction or comparison. The argument
does not hinge upon whether the highest-spending consumers do something different from the rest.
Rather, all consumers are lumped together in the argument.

Takeaways for Find the Assumption Questions

Most of the time, an FA question stem will contain some form of the word "assumption." Occasion-
ally, the question may ask for a new premise that is "required" to draw the conclusion or will help the
conclusion to be "more properly drawn."

Our goal is to find the core (conclusion plus major premises) and brainstorm assumptions while laying
out the core.

Correct answers will represent something that the author must believe to be true in order to draw his or
her conclusion.

If we get stuck between two answers, we can try the Negation technique: negate each answer and see
whether doing so weakens the conclusion; the one that weakens the conclusion is the right answer.

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Assumptions

Trap answer types include:

Out of Scope: goes beyond the scope of the argument, doesn't address or affect the
conclusion

Reverse Logic: does the opposite of what we want (on FA questions, a reverse logic trap
would make the conclusion weaker, not stronger)

Irrelevant Distinction or Comparison: makes a distinction or comparison that doesn't
matter between two groups

Evaluate the Argument Questions

For Evaluate questions, our first step is still to find an assumption, but we have to do a little more work
after finding the assumption. At heart, we are asked what additional information would help us to try
to determine whether the assumption is valid or invalid.

Most Evaluate question stems will contain one of the following:

• some form of the word "evaluate"

some form of the word "determine"

• language asking what would be "useful to know (or establish)" or "important to know"

For example, an Evaluate question stem might ask:

"Which of the following must be studied in order to evaluate the argument?"

"Which of the following would it be most useful to know in determining whether the
mayor's plan is likely to be successful?"

Occasionally, an Evaluate question will use different wording from the above, but the question will still
get at the same overall idea — what is relevant to consider or important to research or understand in
making some decision or evaluating some claim?

The "Two Paths" Strategy

Evaluate answers will often be in the form of a question or in the form "Whether <a certain thing is one
way or the other>." For example, let's say we're given this argument:

In order to increase its profits, MilICo plans to reduce costs by laying off any non-
essential employees.

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Chapter 4

Let's see. According to the argument:

MillCo will lay off non-essential employees reduce costs -» increase profits

Does that sound like a good plan? What is MillCo assuming in claiming that laying off non-essential
employees will result in increased profits?

Profits are a measure of revenues minus costs so, for one thing, MillCo is assuming that revenues wont
drop a lot as a result of these layoffs. If revenues dropped as much as or more than the expected cost
savings, then MillCo's profits wouldn't increase.

An Evaluate question would ask us what would be most important to know in order to evaluate Mill-
Co's plan. A correct answer might read:

Whether revenues will be affected adversely enough to threaten MillCo's profit
structure.

There are two possible paths to examine, yes or no:

Yes, MillCo's revenues will be affected adversely enough. In this case, MillCo's argu-
ment is weakened — the plan to increase profits is less likely to work.

No, MillCo's revenues won't be affected adversely enough. In this case, MillCo's argu-
ment is strengthened — the plan to increase profits might work.

This answer choice, then, is designed to test the assumption; it helps to determine whether the assump-
tion is valid. The correct answer should be structured in such a way that there are at least two possible
"paths" — one path will strengthen the argument, and the other will weaken it.

The incorrect answers will also be presented in this "two paths" format, with one key distinction: the
two paths won't lead in two different directions (strengthening and weakening the argument). What if
we had this answer choice?

Whether MillCo might reduce its costs by eliminating some health insurance benefits.

Let's evaluate the two paths:

Yes, MillCo can reduce costs by eliminating some health benefits. How will this affect
the given plan to lay off employees? It doesn't — it isn't part of the plan at all.

No, MillCo cannot reduce costs by eliminating some health benefits. Again, this
doesn't affect the plan given in the argument.

This incorrect answer choice is trying to distract us by offering a different way to increase profits. . . but
we aren't asked to find alternate ways to increase profits. We're asked to evaluate whether the existing

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Assumptions

argument is valid. We don't know any more than we did about whether MillCos plan (reduce employees
reduce costs -» increase profits) will work.

On Evaluate questions, we're going to do what we do on all Assumption Family questions:

(1) find the core (conclusion plus major premises), noting this on our scrap paper

(2) brainstorm any assumptions we can

Then were going to look for an answer that addresses one of our assumptions (if we've been able to
brainstorm the right one!). The correct answer should offer at least two different "paths," one that
would make the argument stronger and one that would make the argument weaker.

Let's try a full example; set your timer for 2 minutes and pick an answer before you read the explanation!

Editorial: In order to preserve the health of its local economy, Metropolis should
not permit a CostMart warehouse department store to open within city limits.
It has been demonstrated that when CostMart opens a warehouse department
store within a city, the bankruptcy rate of local retailers increases in that city by
twenty percent over the next several years.

Which of the following questions would be most useful for evaluating the conclu-
sion of the Editorial?

(A) Does the bankruptcy rate of local retailers in a city generally stabilize several
years after a CostMart warehouse department store opens?

(B) Do most residents of Metropolis currently do almost all of their shopping at
stores within the city limits of Metropolis?

(C) Have other cities that have permitted CostMart warehouse department
stores within city limits experienced any economic benefits as a result?

(D) Is the bankruptcy rate for local retailers in Metropolis higher than in the aver-
age city that has permitted a CostMart warehouse department store within
city limits?

(E) Does CostMart plan to hire employees exclusively from within Metropolis for
the proposed warehouse department store?

Step 1 : Identify the question.

Which of the following ques- Ev A B C D E The language "most useful" and

tions would be most useful for "evaluating tells me that this is

evaluating the conclusion of the an Evaluate question. I'll write

Editorial? down "Ev" to indicate that.

Assumptions

Chapter 4

Step 2: Deconstruct the argument

Editorial: In order to preserve
the health of its local economy,
Metropolis should not permit
a CostMart warehouse depart-
ment store to open within city
limits.

It has been demonstrated that
when CostMart opens a ware-
house department store within a
city, the bankruptcy rate of local
retailers increases in that city
by twenty percent over the next
several years.

(brainstorm assumptions)

A B C D E

)M ban CM in city -» help loc
econ

Ev A B C D E

)M ban CM in city help loc
econ

if new CM store bnkrpt
locals t 20% for years

Ev A B C D E
©M ban CM in city help loc

econ

if new CM store -> bnkrpt
locals t 20% for years

[any good results?]

"In order to" means that some-
thing is going to cause this. Okay,
the author is saying that M
shouldn't let CM into the city so
that M can preserve the health of
the local economy. That's causa-
tion and kind of sounds like a
conclusion.

Okay, there's a bad economic
outcome for local retailers when a
new CM store opens. So certainly
this is evidence that supports the
authors claim that preventing
CM from opening a store will
preserve the local economy. This is
a premise, so the previous sentence
was the conclusion.
Are there any good economic
results when CM opens a store?
Maybe there are some bad and
good results. . . and maybe the
good results could outweigh the
bad.

Step 3: State the Goal.

When CM opens a new store, there's at least one bad economic outcome. The author concludes that prevent-
ing CM from opening a new store will preserve a good local economy.

I need to find an answer that will have two possible paths — one way will strengthen the author's claim, and
the other way will weaken it. Possibly, the answer might have something to do with the assumption I brain-
stormed — could there be both good and bad possible results from a new CM store?

';Z r : : V'--- ■• - -

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Step 4: Work from wrong to right

(A) Does the bankrupt-
cy rate of local retailers
in a city generally sta-
bilize several years after
a CostMart warehouse
department store opens?

(B) Do most residents of
Metropolis currently do
almost all of their shop-
ping at stores within the
city limits of Metropo-
lis?

(C) Have other cities
that have permitted
CostMart warehouse
department stores
within city limits expe-
rienced any economic
benefits as a result?

(D) Is the bankruptcy
rate for local retailers in
Metropolis higher than
in the average city that
has permitted a Cost-
Mart warehouse depart-
ment store within city
limits?

(E) Does CostMart
plan to hire employees
exclusively from within
Metropolis for the
proposed warehouse
department store?

A B C D E

)M ban CM in city -> help
loc econ

if new CM store -> bnkrpt
locals t 20% for years

[any good results?]
Ev A B C D E

M ban CM in city help
loc econ

if new CM store bnkrpt
locals t 20% for years

[any good results?]
Ev A B C D E

©M ban CM in city -> help
loc econ

if new CM store bnkrpt
locals t 20% for years

[any good results?]
Ev A B C B E

©M ban CM in city -» help
loc econ

if new CM store bnkrpt
locals T 20% for years

[any good results?]

If yes, then the bad result wouldn't continue
to happen over time. . . but it would still hap-
pen in the first place. If no, then the bad re-
sult would keep happening over time. Either
way, there is a bad result for at least a few
years, so both "paths" strengthen the authors
conclusion.

If yes, then. . . I'm not sure what this has to
do with the conclusion. If some stores go out
of business, then people will have to switch
stores? Okay, but that doesn't impact the city's
overall economic situation — either there are
local retailers or there's the CM store in the
city (or both).

If yes, then that would be a reason to let
CM open a store (because economic benefits
would help to "preserve the health of the local
economy"); that weakens the author's argu-
ment. If no, there are no benefits to a CM
store, then this strengthens the author's claim.
This one is looking pretty good.

If yes, then. . . would that make local stores
even more likely to go out of business? I'm not
sure — I don't know why they're going out of
business now. This doesn't seem to affect the
conclusion one way or the other.

A B C © E

©M ban CM in city -» help
loc econ

if new CM store bnkrpt
locals t 20% for years

[any good results?]

This one could be good, too. If yes, then that
would be an economic benefit — jobs are
good! If no, then. . . hmm. . . it's not bad neces- j
sarily but it's not good either.

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(compare C and E) Ev A6©B£ Wait. For E, if some stores are going out

©M ban CM in city -> help of 1 ™™*' that ^ans people losing jobs.

i There's only a benefit to the new CM store

loc econ J J

adding jobs if it adds even more jobs than are
if new CM store -> bnkrpt i 0$t So t /, ere > s no definite benefit given in E,
locals t 20% for years but there is in C Tricky> C it fc

[any good results?]

Common Trap Answers

Answer choice E in the last question was a very tricky trap. How do they get us to pick wrong answers
on Evaluate questions?

Out of Scope: don't make additional assumptions! Answer E presented us with something that seemed
like a benefit at first, until we realized that we had to make an additional assumption in order to know
that we definitely had a benefit. We shouldn't have to make additional assumptions; the answer should
work "as is."

Irrelevant Distinction or Comparison: we saw this trap for the first time in our Find the Assumption
example earlier in the chapter. In the above problem, Answer D does discuss something mentioned
by the argument — bankruptcy — but tries to compare a no-CostMart-in-Metropolis scenario with a
CostMart-in-other-cities scenario, both of which are not the scenario we want to discuss: the scenario in
which CostMart does open up in Metropolis.

Takeaways for Evaluate Questions

As always, we use the question stem to identify the question type. On Evaluate questions, the question
stem will likely contain some form of the word "evaluate," "determine," or "useful (or important) to
know."

Our goal is to find a "two-path" answer: an answer that can be interpreted in two ways, one of which
will strengthen the conclusion and the other of which will weaken the conclusion.

Trap answers will try to get us to make additional assumptions — these answers are actually out of
scope — or to make an irrelevant distinction or comparison between two things that are not the focus
of the argument's conclusion.

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Assumptions

■ 1 !

(A \ j

Flaw Questions

Flaw Questions are the least common of the five Assumption Family question types. The question
stems will almost always contain some form of the word "flaw," but we have to be careful because
Weaken the Conclusion questions can also contain the word "flaw" in the question stem.

Weaken questions will also contain "if true" language; Flaw questions will not contain this language.

Flaw

Weaken

Look for this first:

contains the word "flaw" but NOT "if true"
language

contains the word "flaw" AND the words "if
true" (or an equivalent synonym)

If you re still not sure, try this:

answer choices are a bit more abstract, similar to
but not as abstract as Structure Family questions

answer choices represent a new piece of informa-
tion (see next chapter for more)

Example

Which of the following indicates a flaw in the
reasoning above?

Which of the following, if true, would indicate a
flaw in the teacher's plan?

On occasion, a Flaw question may not contain a synonym of the word "flaw," such as "vulnerable to
criticism."

As with the other Assumption Family questions, Flaw questions will contain a conclusion, and we will
want to brainstorm some assumptions if we can. The correct answer will have something to do with an
assumption, but rather than articulating the assumption (which would help to strengthen the argu-
ment), we are looking for wording that indicates why it is flawed thinking to believe that this assump-
tion is true.

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Chapter 4

For example:

Pierre was recovering from the flu when he visited Shelley last week, and now
Shelley is showing signs of the flu. If Pierre had waited until he was no longer
contagious, Shelley would not have become ill.

The author is assuming that Pierre was the one to infect Shelley. The author is also assuming that there
is no other way Shelley could have gotten sick. Perhaps it is flu season, and many people with whom
Shelley comes in contact have the flu!

The correct answer might be something like:

The author fails to consider that there are alternate paths by which Shelley could have
become infected.

Contrast that language with the assumption itself: the author assumes that only Pierre could have in-
fected Shelley. If that's true, then that piece of information strengthens the author s argument. When we
take the same information, though, and flip it around into a flaw, we harm the author s argument:

Pierre was recovering from the flu when he visited Shelley last week, and now Shelley
is showing signs of the flu. If Pierre had waited until he was no longer contagious,
Shelley would not have become ill.

Assumption

Flaw

Only Pierre could have infected Shelley.

The author fails to consider that there are alter-
nate paths by which Shelley could have become
infected.

The argument is made stronger.

The argument is made weaker.

In sum, we can think of Flaw questions as the "reverse" of Assumption questions. The answer still
hinges on an assumption, but the correct answer will word that assumption in a way that hurts the
argument.

In addition, the answer choice language may be a bit more abstract than the answer choices we see on
other Assumption Family questions. Often, the answer choices will talk about what the author "fails to
consider (or establish)," "does not specify (or identify)," or something along those lines.

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Assumptions

Lets take a look at a full example.

Environmentalist: Bando Inc's manufacturing process releases pollution into the
atmosphere. In order to convince the company to change processes, we will orga-
nize a boycott of the product that represents its highest sales volume, light bulbs.
Because Bando sells more light bulbs than any other product, a boycott of light
bulbs will cause the most damage to the company's profits.

The environmentalist's reasoning is flawed because it fails to

(A) allow for the possibility that Bando may not want to change its manufactur-
ing process

(B) does not supply information about other possible ways for Bando to reduce
pollution

(D) identify any alternative methods by which to convince Bando to change its
manufacturing process

(E) consider that a boycott may take too long to achieve its purpose

Step 1: Identify the question.

The environmentalists reason-
ing is flawed because it fails to

Step 2: Deconstruct the argument

Environmentalist: Bando Incs
manufacturing process releases
pollution into the atmosphere.
In order to convince the com-
pany to change processes, we
will organize a boycott of the
product that represents its high-
est sales volume, light bulbs.

Fl A B C D E The word "flawed" tells me this is either
a Flaw or Weaken question. "If true" does
not appear, so this is a Flaw question. I'll
write down "Fl" on my scrap paper.

Fl A B C D E
E: B MP -> atmo poll

Fl A B C D E

E: B MP atmo poll

boyc LB (t sales) -> conv B
A MP

This is a fact (we'll assume the E
is telling the truth).

Okay, here's a plan, so its likely
a conclusion. They think if they
boycott something, B might
change its MP. So they're going to
boycott LBs because B sells more
LBs than anything else.

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Because Bando sells more light
bulbs than any other product, a
boycott of light bulbs will cause
the most damage to the com-
pany's profits.

Fl A B C D E
E: B MP -» atmo poll
©boyc LB (t sales)

conv

A MP

B sells t LBs -» boyc -» t
damage to prof

Another claim. Because they sell
more LBs than anything else,
the E figures that a boycott of
LBs will do the most damage to
profits. Profits? How profitable
are the LBs?

Okay, the conclusion was the
previous sentence, because all of
this is designed to convince B to
change its MP.

Step 3: State the Goal

Long one. Okay, E doesn't like that B pollutes. B sells more LBs than any other product, so E wants to boycott
the LBs because that will do the most damage to B's profits (according to E, anyway. . .), and then E hopes this
will all cause B to change its MP.

I need to find an answer that will articulate a flaw in that reasoning. I've already thought of one. The E is
assuming that just because B sells more LBs than anything else, B is also earning the most profits from LB.
But there's no evidence there to support that. Another might be that consumers might not actually agree to
boycott B.

Step 4: Work from wrong to right

(A) allow for the possibility
that Bando may not want
to change its manufacturing
process

(B) does not supply informa-
tion about other possible
ways for Bando to reduce
pollution

Fl A B C D E

E: B MP -» atmo poll

)boyc LB (T sales) -> conv
B A MP

B sells t LBs -» boyc -* T

damage to prof

Fl ABCDE

E: B MP -> atmo poll

)boyc LB (T sales) conv
B AMP

B sells t LBs -» boyc -» t
damage to prof

If anything, you could argue that the E
is assuming B will not want to change
— that's why the E thinks he has to
organize a boycott to change B's mind!

In the real world, I agree that E should
explore all possible ways. . . but the
question asks me to find a flaw in this
particular plan about the boycott. This
doesn't apply to that plan.

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(D) identify any alterna-
tive methods by which to
convince Bando to change its
manufacturing process

(E) consider that a boycott
may take too long to achieve
its purpose

Fl AfiCDE

E: B MP -> atmo poll

)boyc LB (t sales) conv
B AMP

B sells t LBs -» boyc -* t

damage to prof

Fl AfiCBE

E: B MP atmo poll

)boyc LB (f sales) -» conv
BAMP

B sells t LBs -> boyc t

damage to prof

Fl AB©BE

E: B MP -» atmo poll

)boyc LB (t sales) conv
BAMP

B sells t LBs -» boyc -» T
damage to prof

This sounds kind of like what I said be-
fore. It's a little abstract, so I'm not sure
I fully understand all of it, but it does
say that sales aren't necessarily propor-
tional to profits, so I'll keep this one in.

This is like answer B. It'd be good in
general for E to do this. . . but this doesn't
help us figure out a flaw in the boycott
plan specifically.

I think what really matters is whether
the plan is going to work at all, not how
long it takes. The argument doesn't have
any requirements about how long it will
take to get B to change its process.

Common Trap Answers

The most common trap on Flaw questions involves making an irrelevant distinction or comparison:

• discussing alternate plans or paths when we were asked to comment on the given plan
(similar to answers B and D in the above example)

• brings up a detail or distinction that does not actually affect the conclusion; similar to
choice E in the above problem

Flaw questions may also occasionally use Reverse Logic, similar to answer choice A in the above ex-
ample.

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Takeaways for Flaw Questions

We recognize Flaw Questions by use of the word "flaw" and the absence ofzny "if true" language. On
occasion, the word "flaw" may be replaced by a synonym, such as "vulnerable to criticism."

On Flaw Questions, we want to find the conclusion and quickly brainstorm any assumptions we can.
The correct answer will be tied to an assumption, but it will be worded to highlight the flaw in assum-
ing something to be true; it will hurt the argument.

The most common trap answers typically involve making some kind of irrelevant distinction or com-
parison. The answer might address something in a premise that doesn't affect the conclusion, or it may
go down a different path entirely when we were asked to comment on a specific plan.

MANHATTAN

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Assumptions

Problem Set

Chapter 4

Answer each question using the 4-step CR process. Check your answer after each question. As you
improve, consider timing yourself; critical reasoning questions need to be completed in an average of 2
minutes.

1. MTC & Asthma

Methyltetrachloride (MTC) is a chemical found in some pesticides, glues, and seal-
ants. Exposure to MTC can cause people to develop asthma. In order to halve the
nation's asthma rate, the government plans to ban all products containing MTC.

The government's plan to halve the nation's asthma rate relies on which of the fol-
lowing assumptions?

(A) Exposure to MTC is responsible for no less than half of the nation's asthma
cases.

(B) Products containing MTC are not necessary to the prosperity of the Ameri-
can economy.

(D) Exercise and proper nutrition are helpful in maintaining respiratory health.

(E) Dust mites and pet dander can also cause asthma.

Recently, the tuition at most elite private colleges has been rising faster than infla-
tion. Even before these increases, many low and middle income families were un-
able to afford the full tuition costs for their children at these institutions of higher
learning. With the new tuition increases, these colleges will soon cater solely to
students with affluent family backgrounds.

Which of the following would it be most useful to determine in order to evaluate
the argument?

(A) Whether students from affluent families are more likely to prefer public or
private colleges

(B) Whether students from low and middle income families are qualified to at-
tend elite private colleges

(D) Whether tuition costs at elite public colleges have also been rising faster
than inflation

(E) Whether grants or scholarships are earmarked for students from economi-
cally disadvantaged families

2. Tuition

117

GMAT

Chapter 4

Assumptions

3. Charity

Studies show that impoverished families give away a larger percentage of their
income in charitable donations than do wealthy families. As a result, fundraising
consultants recommend that charities direct their marketing efforts toward indi-
viduals and families from lower socioeconomic classes in order to maximize the
dollar value of incoming donations.

Which of the following best explains why the consultants' reasoning is flawed?

(A) Marketing efforts are only one way to solicit charitable donations.

(B) Not all impoverished families donate to charity.

(C) Some charitable marketing efforts are so expensive that the resulting dona-
tions fail to cover the costs of the marketing campaign.

(D) Percentage of income is not necessarily indicative of absolute dollar value.

(E) People are more likely to donate to the same causes to which their friends
donate.

4. Oil and Ethanol

Country N's oil production is not sufficient to meet its domestic demand. In order
to sharply reduce its dependence on foreign sources of oil, Country N recently
embarked on a program requiring all of its automobiles to run on ethanol in ad-
dition to gasoline. Combined with its oil production, Country N produces enough
ethanol from agricultural by-products to meet its current demand for energy.

Which of the following must be assumed in order to conclude that Country N will
succeed in its plan to reduce its dependence on foreign oil?

(A) Electric power is not a superior alternative to ethanol in supplementing
automobile gasoline consumption.

(B) In Country N, domestic production of ethanol is increasing more quickly
than domestic oil production.

(D) In Country N, gasoline consumption is not increasing at a substantially
higher rate than domestic oil and ethanol production.

(E) Ethanol is as efficient as gasoline in terms of mileage per gallon when used
as fuel for automobiles.

MANHATTAN
GMAT

Assumptions

Chapter 4

5. Exchange Student

Student Advisor: One of our exchange students faced multiple arguments with
her parents over the course of the past year. Not surprisingly, her grade point
average (GPA) over the same period showed a steep decline. This is just one
example of a general truth: problematic family relationships can cause significant
academic difficulties for our students.

The claim by the Student Advisor would be more properly drawn if which of the
following were inserted into the argument as an additional premise?

(A) Last year, the exchange student reduced the amount of time spent on aca-
demic work, resulting in a lower GPA.

(B) The decline in the GPA of the exchange student was not the reason for the
student's arguments with her parents.

(D) If proper measures are not taken, the decline in the student's academic per-
formance may become irreversible.

(E) Fluctuations in academic performance are typical for many students.

6. Food Allergies

Food allergies account for more than thirty thousand emergency department
visits each year. Often, victims of these episodes are completely unaware of their
allergies until they experience a major reaction. Studies show that ninety percent
of food allergy reactions are caused by only eight distinct foods. For this reason,
individuals should sample a minuscule portion of each of these foods to deter-
mine whether a particular food allergy is present.

Which of the following must be studied in order to evaluate the recommendation
made in the argument?

(A) The percentage of allergy victims who were not aware of the allergy before a
major episode

(B) The percentage of the population that is at risk for allergic reactions

(D) Whether an allergy to one type of food makes someone more likely to be
allergic to other types of food

(E) Whether ingesting a very small amount of an allergen is sufficient to pro-
voke an allergic reaction in a susceptible individual

MANHATTAN
GMAT

Chapter 4

Assumptions

7. News War

For several years, Nighttime News attracted fewer viewers than World News,
which broadcasts its show at the same time as Nighttime News. Recently, the pro-
ducers of Nighttime News added personal interest stories and increased coverage
of sports and weather. The two programs now have a roughly equal number of
viewers. Clearly, the recent programming changes persuaded viewers to switch
from World News to Nighttime News.

The conclusion above is properly drawn if which of the following is assumed?

Viewers are more interested in sports and weather than in personal interest
stories.

The programming content of Nighttime News is more closely aligned with
the interests of the overall audience than is the content of World News.
Some World News viewers liked the new Nighttime News programming bet-
ter than they liked the World News programming.
There are other possible causes for an increase in the number of viewers of
Nighttime News, including a recent ad campaign that aired on many local
affiliates.

The quality of World News will remain constant even if Nighttime News
improves.

8. Five-Step Process

Manager: the new manufacturing process should save us time overall, even
though the first step of the five-step process will take twice as long as it does
under the old process. Under the new process, far fewer of the components will
be found defective, and the sole purpose of steps two and three under the old
process is to weed out defective components. As a result, we should be able to
eliminate two of the five steps in the existing manufacturing process.

Which of the following would be most useful in evaluating the claim made in the
argument?

(A) Whether factory workers will require training in order to use the new manu-
facturing process

(B) Whether the new process is likely to introduce deficiencies or imperfections
that must be corrected

(D) Whether a third manufacturing process would save even more time than
both the old and new manufacturing processes

(E) Whether saving time with the new manufacturing process will ultimately
lead to cost savings for the company

MANHATTAN
GMAT

Assumptions

Chapter 4

9. Genetics

Two genes, BRCA1 and BRCA2, are linked to hereditary breast cancer. Therefore, in
order to decrease the annual number of mammogram tests administered across
a population and to more accurately assess a woman's individual risk of breast
cancer, all women should be tested for these genes.

Which of the following is an assumption on which the argument depends?

(A) Some of the women who are tested for the two genes will subsequently
undergo mammograms on a less frequent basis than they used to.

(B) The majority of breast cancer patients have no family history of the disease.

(D) Women who have these genes have an 80 percent chance of getting breast
cancer, while women who do not have these genes have only a 10 percent
chance of getting breast cancer.

(E) The presence of BRCA1 and BRCA2 can explain up to 50 percent of heredi-
tary cases.

MANHATTAN

GMAT

Assumptions

Chapter 4

Solutions

A B C D E

1. MTC & Asthma: The correct answer is A.

Step 1: Identify the question.

The government's plan to halve FA
the nations asthma rate relies on
which of the following assump-
tions?

Step 2: Deconstruct the argument.

Methyltetrachloride (MTC) is a FA A B C D E

chemical found in some pesti-
cides, glues, and sealants.
Exposure to MTC can cause
people to develop asthma.

In order to halve the nations
asthma rate, the government
plans to ban all products con-
taining MTC.

MTC chem

FA A B C D E

MTC chem -» asthma
FA A B C D E

MTC chem asthma

©ban MTC -* Vi asthma rate

Step 3: State the Goal.

Asks for the "assumption"; this is i
Find the Assumption question.

This is just a fact — background
or maybe a premise.

Another fact but it's specifically a
bad fact. This is likely a premise.

Okay, the government has a plan
to ban MTC , and the result will
be (they claim) that the asthma
rate will be cut in half There
are no numbers or anything to
support that. Are a lot of people
exposed now? What percentage of
those who develop asthma were
exposed? Etc.

The government claims that it can halve the asthma rate by banning MTC, but it gives absolutely no evi-
dence or numbers to support halving the rate.

I need to find an answer that supports the idea that they can halve the asthma rate — maybe that a very large
percentage of people who develop asthma were exposed to MTC or something like that.

MANHATTAN
GMAT

er 4

Assumptions

Step 4: Work from wrong to rig ht.

(A) Exposure to MTC
is responsible for no less
than half of the nations
asthma cases.

(B) Products containing
MTC are not necessary
to the prosperity of the
American economy.

(D) Exercise and proper
nutrition are helpful in
maintaining respiratory
health.

(E) Dust mites and pet
dander can also asthma.

FA ABCDE

MTC chem -» asthma

©ban MTC Vi asthma
rate

FA ABCDE

MTC chem -» asthma

©ban MTC -» Vi asthma
rate

FA ABCDE

MTC chem asthma

©ban MTC -» Vi asthma
rate

FA ABCDE

MTC chem asthma

©ban MTC -» Vi asthma
rate

FA ®B € D E

MTC chem asthma

©ban MTC -» Vi asthma
rate

This sounds similar to what I said. Let's see.
If MTC actually is responsible for at least half
of asthma cases, then getting rid of it would
get rid of all those cases as well. This one looks
pretty good.

Prosperity of the economy? They're just trying
to distract me by making me think of a reason
why we might want to use MTC. The conclu-
sion is about halving the asthma rate, and
this doesn't affect that conclusion.
If asthma rates are really high, then that sup-
ports the idea of wanting to lower them. But
that's not what I'm trying to do — the author
doesn't HAVE to believe this is true. Plus it
says nothing about whether MTC is the cause.
Distraction! Nothing about how or whether
MTC causes asthma, or whether getting rid of
I MTC will lower asthma rates.

Distraction! Nothing about how or whether
MTC causes asthma, or whether getting rid of
MTC will lower asthma rates.

2. Tuition: The correct answer is E.
Step 1: Identify the question.

Which of the following would it
be most useful to determine in
order to evaluate the argument?

Step 2: Deconstruct the argument.

Recently, the tuition at most
elite private colleges has been
rising faster than inflation.

ABCDE

Ev ABCDE
EPC t tuit>infl

Contains the words "evaluate"
and "useful to determine" — this
is an Evaluate question.

Fact: tuition at this specific type
of school has been going up even
faster than inflation.

MANHATTAN
GMAT

Assumptions

Chapter 4

Even before these increases,
many low and middle income
families were unable to afford
the full tuition costs for their
children at these institutions of
higher learning.
With the new tuition increases,
these colleges will soon cater
solely to students with affluent
family backgrounds.

And people without much money
already couldn't afford these
schools, even before the tuition
went up. Another fact.

This must be the conclusion
because the other two were facts.
Basically, they're saying that only
wealthy students are going to be
able to afford these schools now.

Ev A B C D E

EPC t tuit > infl

B4: I + mid inc fams cant
afford

Ev A B C D E

EPC t tuit > infl

B4: I + mid inc fams cant
afford

©EPC will have only rich
students

Step 3: State the Goal.

This is an Evaluate question, so I need to find an answer that will help to determine whether or not the
conclusion is likely to be valid. The correct answer will have "two paths": one path will make the conclusion a
little more likely to be valid, and the other will make the conclusion a little less likely to be valid.

The conclusion is that only wealthy students are going to be able to go to these EPCs. What is the author as-
suming? Absolutely none of the low or middle income students can afford these schools. Non-wealthy students
arent going to be taking out loans, or working their way through school, or finding some other way to cover
the tuition costs.

Step 4: Work from wrong to right.

(A) Whether students
from affluent families
are more likely to prefer
public or private colleges

(B) Whether students
from low and middle
income families are
qualified to attend elite
private colleges

Ev A B C D E

EPC t tuit > infl

B4: 4 + mid inc fams cant
afford

©EPC will have only rich
students

Ev AfiCDE

EPC t tuit > infl

B4: I + mid inc fams cant
afford

©EPC will have only rich
students

If affluent students prefer public colleges, that
doesnt change the fact that the private colleges
charge a lot of money and poorer students
cant afford them. If affluent students prefer
private colleges, that also doesnt change the
same fact.

If these students are not qualified to attend
the EPCs, that doesnt change anything about
the tuition issue. If these students are quali-
fied, that also doesnt change the tuition issue
(though it makes it seem unfair that the EPCs
charge so much money!).

GMAT

125

Assumptions

(D) Whether tuition
costs at elite public col-
leges have also been ris-
ing faster than inflation

(E) Whether grants or
scholarships are ear-
marked for students
from economically
disadvantaged families

Ev A B € D E

EPC t tuit > infl

B4: I + mid inc fams cant
afford

©EPC will have only rich
students

Ev A B € © E

EPC t tuit > infl

B4: I + mid inc fams can't
afford

©EPC will have only rich
students

Ev A B € ©(E)

EPC t tuit > infl

B4: I + mid inc fams cant
afford

©EPC will have only rich
students

This answer makes a distinction between
low and middle income families, but the
argument doesn't distinguish between these
| two groups — it combines them. Logically,
it would make sense that the less money a
family has, the less likely it could afford the
tuition... but this doesnt change anything
about the basic argument that low and mid-
dle income families cant afford the tuition.
If they have, then maybe that means lower-
income students cant afford those schools
either. . . but it might not mean anything,
because perhaps the public schools have lower
tuition fees in the first place. If rates have not
been rising as fast at public colleges. . . that
doesnt affect the argument's conclusion at all.

If there are grants and scholarships for
lower-income students, then perhaps they can
afford to attend the EPCs — this hurts the
argument's conclusion. If there are not grants
and scholarships for these students, then the
argument's conclusion is more likely to be
true: these students won't be able to afford
these colleges. The "two paths" on this answer
do lead to strengthening the conclusion on one
hand and weakening it on the other.

3. Charity: The correct answer is D.
Step 1: Identify the question.

Which of the following best
explains why the consultants'
reasoning is flawed?

A B C D E

The word " flawed" indicates that
this is either a Flaw or Weaken
question. The lack of the words
"if true" (or an equivalent) means
that this is a Flaw question.

MANHATTAN
GMAT

Assumptions

Chapter 4

Step 2: Deconstruct the argument.

Studies show that impover-
ished families give away a larger
percentage of their income in
charitable donations than do
wealthy families.

As a result, fundraising consul-
tants recommend that charities
direct their marketing efforts
toward individuals and fami-
lies from lower socioeconomic
classes in order to maximize the
dollar value of incoming dona-
tions.

F A B C D E

poor donate > % inc than
rich

F A B C D E

poor donate > % inc than
rich

©FC: to get most $, char shld
focus on I inc ppl

This is a fact. It's impressive that
the poor donate anything, but if
they do donate anything, then this
fact makes sense because donating
$100 is a much greater percentage
of your income if you don't have
much income.

This is the conclusion. Based on
the percentage info, the FCs are
saying that the charities should
focus on lower income people. . .
but the FCs are assuming that
"greater percentage" equals more
money. A very rich person might
donate $10 million, a small
percentage of income but a very
large sum.

Step 3: State the Goal.

For flaw questions, it's important to find the conclusion and brainstorm any assumptions, if I can. I need to
find an answer that hurts the argument or shows why the argument is not a good argument.

In this case, the FCs are recommending that the charities target lower income families in order to maximize
the number of dollars they get in donations. Vve identified one potential assumption: the FCs assume that
donating a greater percentage of income also means donating a greater dollar amount collectively. If that's not
actually the case, then that's a flaw.

Step 4: Work from wrong to right.

(A) Marketing efforts
are only one way to
solicit charitable dona-

A B C D E

tions.

(B) Not all impover-
ished families donate to
charity.

poor donate > % inc than
rich

©FC: to get most $, char
shld focus on I inc ppl
F A B C D E

This might be true, but it just indicates
that there might be other ways, in addition
to marketing efforts, to raise money. That
doesn't affect the FCs recommendation to
target lower income families in particular.

poor donate > (
rich

inc

than

©FC: to get most $, char
shld focus on i> inc ppl

I'm sure this is true, but how does it affect the
conclusion? It doesn't. The argument never
claims that ALL impoverished families donate
to charity — only that, in general, they donate
a larger percentage of income to charity.

GMAT

127

Chapter 4

Assumptions

(C) Some charitable
marketing efforts are
so expensive that the
resulting donations fail
to cover the costs of the
marketing campaign.

(D) Percentage of in-
come is not necessarily
indicative of absolute
dollar value.

(E) People are more
likely to donate to the
same causes to which
their friends donate.

F A B € D E

poor donate > % inc than
rich

)FC: to get most $, char
shld focus on I inc ppl

F A B € D E

poor donate > % inc than
rich

)FC: to get most $, char
shld focus on I inc ppl

F A B €@fi

poor donate > % inc than
rich

)FC: to get most $, char
shld focus on i inc ppl

Oh, maybe this is it. If you spend more on the
marketing than you make from donations,
that cant be a very successful marketing cam-
paign. What was the conclusion again? Oh,
wait, "to maximize the dollar value of dona-
tions. " Whether ther marketing covered costs
isn't part of the conclusion — it just depended
on how much money they get in donations.
Tricky, but not correct.
This is what I was saying before about the
really rich person donating $10 million! You
can have a bunch of low income people give
10% of their income and one billionaire give
9% of her income. . . and the billionaire could
be giving more in terms of absolute dollars.
This indicates the flawed assumption made
by the FCs.

I can believe that this is true, but the argu-
ment doesnt address which causes people
choose for charity. Rather, the argument talks
about amount of money donated.

4. Oil and Ethanol: The correct answer is D.

Step 1; Identify the question.

Which of the following must be
assumed in order to conclude
that Country N will succeed in
its plan to reduce its dependence
on foreign oil?

Step 2: Deconstruct the argument.

Country N's oil production is
not sufficient to meet its domes-
tic demand.

A B C D E

FA A B C D E
N oil prod * dem

! Contains the word "as-
sumed" — this is a Find the As-
sumption question.

They produce oil but cant make
\ enough for their own needs. That
\ must mean they have to import
! some oil.

MANHATTAN
GMAT

Assumptions

Chapter 4

In order to sharply reduce its
dependence on foreign sources
of oil, Country N recently em-
barked on a program requiring
all of its automobiles to run on
ethanol in addition to gasoline.
Combined with its oil produc-
tion, Country N produces
enough ethanol from agricul-
tural by-products to meet its
current demand for energy.

FA A B C D E

N oil prod ^ dem

N req cars eth -» I for. oil

FA A B C D E
N oil prod * dem
N req cars eth -» 1 for. oil
N eth + oil = N s dem now

They're requiring cars to use etha-
nol, and they think that'll lead
to having to use less foreign oil. It
sounds like the cars can still use
gas, though. . .

Okay, so they do make enough
ethanol PLUS oil combined to
satisfy their own needs currently.
The question is whether people are
actually going to use ethanol for
their cars or whether they'll want
to keep using gasoline. And what
if demand changes in future?

Step 3: State the Goal.

Country N thinks it can "sharply reduce" the amount of foreign oil it needs if it starts making people have
cars that use ethanol. Will the plan really work that way? They're assuming people really will start to use the
ethanol. They're also assuming they'll continue to produce enough oil and ethanol in the future.

I need to find an answer that must be true in order to allow the author to draw the above conclusion.

Step 4: Work from wrong to rig ht.

(A) Electric power is not
a superior alternative to
ethanol in supplement-
ing automobile gasoline
consumption.

(B) In Country N,
domestic production
of ethanol is increasing
more quickly than do-
mestic oil production.

FA A B C D E

N oil prod ^ dem

N req cars eth -> I for. oil

N eth + oil = N s dem
now

FA A B C D E

N oil prod * dem

N req cars eth -» I for. oil

N eth + oil = N s dem
now

Electric power? That seems out of scope. We're
supposed to find something that goes with the
plan stated in the argument, and that plan
mentions nothing about electric power.

If this is true, then switching stuff to ethanol
seems like a good call. Does it HAVE to be
true in order to draw the conclusion? What
if the two were increasing at the same rate?
That would be fine, actually. This doesn't
have to be true — so it isn't a necessary as-
sumption.

GMAT

129

Assumptions

(D) In Country N,
gasoline consumption
is not increasing at a
substantially higher rate
than domestic oil and
ethanol production.

FA A B € D E

N oil prod ^ dem

N req cars eth I for. oil

N eth + oil = N s dem
now

FA A B € D E

N oil prod ^ dem

N req cars eth I for. oil

N eth + oil = Ns dem
now

(E) Ethanol is as ef-
ficient as gasoline in
terms of mileage per
gallon when used as fuel
for automobiles.

A fi €©£
N oil prod ^ dem
N req cars eth i for. oil
N eth + oil = Ns dem

now

5. Exchange Student: The correct answer is B.
Step 1: Identify the question.

The claim by the Student
Advisor would be more properly
drawn if which of the following
were inserted into the argument
as an additional premise?

Step 2: Deconstruct the argument.

Student Advisor: One of our ex-
change students faced multiple
arguments with her parents over
the course of the past year.

If this is true, then switching stuff to ethanol
seems like a good call. Does it HAVE to be
true in order to draw the conclusion? No. The
argument only talks about a plan to have cars
start using ethanol.

Hmm. The argument is assuming in gen-
eral that the ethanol + oil production can
keep up with the country's demand. So, yes,
the author would have to assume that gas
consumption isn't increasing at a much faster
rate than production.

Let's try negating this one: If gas consump-
tion WERE increasing at a much higher rate,
what would happen? Oh, they might have to
get more from foreign sources — bingo! Negat-
ing this does weaken the conclusion.
It would be good to know how efficient etha-
nol is compared to gas. . . but does it HAVE
to be true that they're equally efficient? No.
Even if ethanol were less efficient, it's possible
that the country could still produce enough to
meet its needs.

A B C D E

FA A B C D E
SA: st arg par lyr

This is a tough one. They're asking me
to find the answer that can be "inserted
into the argument as a premise. "Do-
ing so makes the claim "more properly
drawn. " This is an example of unusual
wording for a Find the Assumption
question.

This is a fact — background or a
premise.

Assumptions

Chapter 4

Not surprisingly, her grade point
average (GPA) over the same
period showed a steep decline.

This is just one example of
a general truth: problematic
family relationships can cause
significant academic difficulties
for our students.

FA A B C D E
SA: st arg par lyr
GPA 44

FA A B C D E
SA: st arg par lyr
GPA 44
©fam prob -> acad prob

Not only did the student's GPA
go down, but the SA says "not
surprisingly. " Sounds like the SA
is going to conclude something
based on this.

Here we go: the SA claims that
this student's family problems
caused the academic problems.
Maybe there was a different cause.

Step 3: State the Goal.

/ need to find an answer that the author must believe to be true in order to draw this conclusion. The only
thing I can think of right now is very general: if the SA is assuming the family problems were what caused the
academic problems, then the SA is also assuming there wasn't something else causing the academic problems.

Step 4: Work from wrong to right.

(A) Last year, the ex-
change student reduced
the amount of time
spent on academic work,
resulting in a lower
GPA.

(B) The decline in the
GPA of the exchange
student was not the
reason for the students
arguments with her
parents.

FA A B C D E
SA: st arg par lyr
GPA 44
©fam prob -» acad prob

FA A B C D E
SA: st arg par lyr
GPA 44
©fam prob acad prob

FA A B € D E
SA: st arg par lyr
GPA 44
©fam prob ~* acad prob

This would explain why her GPA went
down, which means maybe it didrit actu-
ally have to do with family problems. But
I'm looking for something the author believes
will HELP with the claim that it was family
problems. This answer hurts that claim.
Let's see. This is kind of what I said be-
fore — there is NOT a different cause for the
decline of her GPA.

Let's try negating this. If the student's GPA
went down first and then her parents got mad
at her for that reason, then you can't claim
that the family problems caused the lower
GPA. The SA 's argument would fall apart.
This one looks good.

This doesn't matter. Either it's accurate or
inaccurate. Regardless, it used to be higher
and is now lower, and she and her parents
have been arguing about something. Whether
it's accurate doesn't come into consideration
in the argument.

MANHATTAN
GMAT

Assumptions

(D) If proper measures
are not taken, the
decline in the student s
academic performance

FA A B € B E
SA: st arg par lyr
GPAU

may become irreversible. ©f am pro b -> acad prob
(E) Fluctuations in FA A(B)€ B £

academic performance
are typical for many
students.

SA: st arg par lyr
GPAU
©fam prob -* acad prob

/ could see how this might be true in general,
but this doesnt support the idea that family
problems can cause academic problems. If it
doesnt support that idea, it cant possibly be
the assumption.

I could see how this might be true in general,
but this doesnt support the idea that family
problems can cause academic problems. If it
doesnt support that idea, it cant possibly be
the assumption.

6. Food Allergies: The correct answer is E.
Step 1: Identify the question.

Which of the following must be
studied in order to evaluate the
recommendation made in the
argument?

Step 2: Deconstruct the argument.

Studies show that ninety percent
of food allergy reactions are
caused by only eight distinct
foods.

For this reason, individuals
should sample a minuscule por-
tion of each of these foods to
determine whether a particular
food allergy is present.

A B C D E

Ev A B C D E
FA 30k ER/yr

Ev A B C D E

FA -> 30k ER/yr

ppl don't know till have rx

Ev A B C D E

FA ^ 30k ER/yr

ppl don't know till have rx

only 8 foods -» 90% FA rx
Ev A B C D E

FA -> 30k ER/yr

ppl don't know till have rx

only 8 foods -* 90% FA rx

)ppl shld try tiny bit of 8
foods to see if FA

The words "must be studied" and
"evaluate" indicate that this is an
Evaluate question.

This is a fact.

Fact but more fuzzy. A lot of
people dont know they're allergic
till they have a major reaction.

More facts! That's interesting.
Only 8 foods cause most allergic
reactions.

This is the conclusion. The au-
thors saying we should all try a
tiny bit of these 8 foods to see what
happens. That assumes that we'll
actually have a reaction from a
tiny amount. It also assumes we
wont die from just a tiny amount
(if we are allergic).

Assumptions

Step 3: State the Goal

This is an Evaluate question, so I need to find an answer that will help to determine whether or not the
conclusion is likely to be valid. The correct answer will have "two paths": one path will make the conclusion a
little more likely to be valid and the other will make the conclusion a little less likely to be valid.

In this case, the author recommends that we all try tiny bits of these 8 foods to see whether we're allergic. The
authors assuming that we can tell whether we're allergic from trying just a tiny bit — and also that we wont
die by trying a small amount if we are allergic.

Step 4: Work from wrong to rig ht.

(A) The percentage of
allergy victims who were
not aware of the allergy
before a major episode

(B) The percentage of
the population that is at
risk for allergic reactions

(D) Whether an al-
lergy to one type of food
makes someone more
likely to be allergic to
other types of food

Ev A B C D E

FA ^ 30k ER/yr

ppl don't know till have rx

only 8 foods -» 90% FA rx

©ppl shld try tiny bit of 8 foods
to see if FA

Ev A B C D E

FA -> 30k ER/yr

ppl don't know till have rx

only 8 foods 90% FA rx

©ppl shld try tiny bit of 8 foods
to see if FA

Ev A fi € D E

FA -» 30k ER/yr

ppl don't know till have rx

only 8 foods -» 90% FA rx

©ppl shld try tiny bit of 8 foods
to see if FA
Ev A B € B E

FA 30k ER/yr

ppl don't know till have rx

only 8 foods -» 90% FA rx

©ppl shld try tiny bit of 8 foods
to see if FA

The argument told us that victims "often"
aren't aware of the allergy beforehand.
If I knew that 90% weren't aware, that
would go along with what the argument
already says. If I knew that 50% weren't
aware. . . hmm, that wouldn't change the
argument. In general, knowing the exact
percentage doesn't change anything.
If a really high percentage is at risk for
allergies, then it's probably important to
figure out whether people are allergic. . .
but that doesn't mean that the specific
recommendation in the conclusion here is
a good or bad one. Also, this answer choice
doesn't specifically limit itself to food aller-
gies; it mentions all allergies in general.
If yes, then many people may have already
tried small amounts of these foods. That
doesn't actually tell us, though, whether
the recommendation is a good one. If no,
then it doesn't affect the conclusion at
all — we still don't know whether it's a
good recommendation.

If yes or if no, you'd still want to test
people to see whether they're allergic to
anything. This choice doesn't have "two
paths" that lead to alternate outcomes.

Assumptions

(E) Whether ingesting
a very small amount of
an allergen is sufficient
to provoke an allergic
reaction in a susceptible
individual

Ev A B € B(E)
FA 30k ER/yr
ppl don't know till have rx
only 8 foods -» 90% FA rx

This is one of the things that I said! If yes,
then the authors plan will work: people
! will be able to try small amounts and
determine whether they're allergic. If no,
then the authors plan is not a good one:

^ trying small amounts won t actually help

Oppl shld try tiny bit of 8 foods , , , „ .

^ rr 33 us tell whether we re allergic.

to see if FA

7. News War: The correct answer is C.

Step 1: Identify the question.

The conclusion above is properly
drawn if which of the following |
is assumed?

Step 2: Deconstruct the argument.

For several years, Nighttime
News attracted fewer viewers
than World News, which broad-
casts its show at the same time
as Nighttime News.
Recently, the producers of
Nighttime News added personal
interest stories and increased
coverage of sports and weather.
The two programs now have a
roughly equal number of view-
ers.

Clearly, the recent program-
ming changes persuaded viewers
to switch from World News to
Nighttime News.

A B C D E

FA A B C D E
past: NN< WN

FA A B C D E

past:NN<WN

rec: NN + pers, sp, weath

FA ABCDE

past:NN<WN

rec: NN + pers, sp, weath

now:NN = WN
FA ABCDE

past: NN < WN
I rec: NN + pers, sp, weath

now:NN = WN
©prog A -» switch

; The word "assumed" tells me that
\ this is a Find the Assumption
question.

NN and WN are competitors. In
the past, WN got more viewers.
Facts = premises.

NN added certain new things.

Now, the two are about equal.
; Interesting. Why? So far, all
I premises.

Conclusion! The author is claim-
ing that the new programming
\ things actually caused people to
J switch from one show to the other.
Hmm — that would mean WNs
numbers went down — did they?
Or is it just that NN went up? Or
maybe there's some other reason
\fbr the change entirely.

Assumptions

Chapter 4

Step 3: State the Goal.

The author is claiming specifically that people switched from WN to NN — but there's no evidence for that.
The author is assuming that, ifNN's numbers went up, then WN's numbers went down and that those
people switched to NN (and didn't start watching something else or turn off their TVs entirely!).

The author's also assuming that the reason for the switch was NN's new programming and not something else.

I need to find an answer that represents something the author must believe to be true.

Step 4: Work from wrong to right.

(A) Viewers are more
interested in sports and
weather than in per-
sonal interest stories.

(B) The programming
content of Nighttime
News is more closely
aligned with the inter-
ests of the overall audi-
ence than is the content
of World News.

(C) Some World News
viewers liked the new
Nighttime News pro-
gramming better than
they liked the World
News programming.

(D) There are other
possible causes for an
increase in the number
of viewers of Night-
time News, including
a recent ad campaign
that aired on many local
affiliates.

FA A B C D E
past: NN < WN
rec: NN + pers, sp, weath
now: NN = WN
©prog A -» switch

FA A B C D E

past: NN < WN

rec: NN + pers, sp, weath

now:NN = WN

©prog A -» switch

FA ABCDE

past: NN < WN

rec: NN + pers, sp, weath

now: NN = WN

©prog A -» switch
FA ABCBE

past: NN < WN

rec: NN + pers, sp, weath

now: NN = WN

©prog A -> switch

Hmm. NN added all 3 of these things. Does
the author need to assume that two are more
popular than the third? No — it doesn't mat-
ter as long as the programming in general
did make people switch. Maybe they're trying
to get me to think that the choice is compar-
ing WN and NN — but that's not what this
choice actually says.

This basically says that the audience likes
NNs content better than WN's content. That
could be a reason to switch. Does it absolutely
have to be true? It also addresses the program-
ming issue, so it does seem pretty good — I'll
leave it in for now.

This also talks about liking NN better than
WN. In particular, it says that some WN
viewers decided they liked the new NN stuff
better. That also looks really good. Leave it
in.

"Other possible causes" — oh, no, are all three
of these choices good? Wait a second. I'm read-
ing this backwards. This is saying there are
other reasons why more people are watching
NN, so that would actually hurt the author's
claim that it's because WN viewers switched
due to the programming.

GMAT

135

Chapter 4

Assumptions

(E) The quality of
World News will remain
constant even if Night-
time News improves.

compare B and C

FA ABCBE

past: NN < WN

rec: NN + pers, sp, weath

\ now:NN = WN

©prog A switch
FA AB©BE

past: NN < WN

rec: NN + pers, sp, weath

now: NN = WN

©prog A switch

If this were true, it might help explain why
some people would switch, but does it HAVE
to be true in order to claim that people
already switched due to NNs new program-
ming? No.

Lets try negating B and C.

B: NN content is not more closely aligned
with audience than WN content. Maybe
they're about the same? That doesnt really
hurt the authors argument all that much.

C: None of the WN viewers liked NN better
than WN Wait a second. If NONE of them
liked NN better, why would they switch?
Negating this definitely hurts the argument.
Citisl

8. Five-Step Process: The correct answer is B.
Step 1: Identify the question.

Which of the following would
be most useful in evaluating the
claim made in the argument?

Step 2: Deconstruct the argument.

Manager: the new manufactur-
ing process should save us time
overall, even though the first
step of the five-step process will
take twice as long as it does
under the old process.
Under the new process, far
fewer of the components will
be found defective, and the sole
purpose of steps two and three
under the old process is to weed
out defective components.

A B C D E

Ev A B C D E

M: New MP faster but SI
2x longer

Ev A B C D E

M: New MP faster but SI
2x longer

NMP = I bad parts
OMP S2+3 for bad parts

The language "most useful in
evaluating" indicates that this is
an Evaluate question.

This is a claim. It could be the
conclusion — F 11 have to keep
reading to tell.

This seems to be a combo of a
claim and a fact, but both are
supporting the first sentence.

136

GMAT

Assumptions

As a result, we should be able to
eliminate two of the five steps
in the existing manufacturing
process.

Yes, the first sentence was the con-
clusion. If the other things are all
true, then maybe the NMP will
be faster than the old one.

Ev A B C D E

M: New MP faster but SI
2x longer ©

NMP = 4 bad parts

OMP S2+3 for bad parts

so elim 2 steps for NMP

Step 3: State the Goal.

The manager is claiming that the new process will be faster than the old process. Although the 1st step will
take twice as long under the new process, the manager claims they "should" be able to drop the second and
third steps. If dropping the second and third steps saves even more time than is lost during the first step, then
the manager might be right. . . but the manager is assuming that these other steps will save a lot more time.

Step 4: Work from wrong to rig ht.

(A) Whether factory
workers will require
training in order to use
the new manufacturing
process

(B) Whether the new
process is likely to
introduce deficiencies or
imperfections that must
be corrected

Ev A B C D E

M: New MP faster but Si
= 2x longer ©

NMP = I bad parts

OMP S2+3 for bad parts

so elim 2 steps for NMP
Ev ABCDE

M: New MP faster but SI
= 2x longer ©

NMP = I bad parts

OMP S2+3 for bad parts

so elim 2 steps for NMP

If they do. . . that may or may not affect how
much time the process takes. If they dont, I
still dont know anything more about how
much time the new process is going to take
versus the old process.

If the new process also introduces problems
that then need to be fixed, then perhaps they
cant drop steps two and three, or perhaps
they have to introduce other new steps to fix
the deficiencies. . . either of which would add
time to the new process, making it less likely
that the new process will save time. If the new
process does not introduce new imperfections
that need to be fixed, then that increases the
likelihood that the new process will save time.

Assumptions

(D) Whether a third
manufacturing process
would save even more
time than both the old
and new manufacturing
processes

(E) Whether saving
time with the new
manufacturing process
will ultimately lead

to cost savings for the
company

Ev ABODE

M: New MP faster but Si
= 2x longer ©

NMP = i bad parts

OMP S2+3 for bad parts

so elim 2 steps for NMP

Ev ABODE

M: New MP faster but SI
= 2x longer ©

NMP = I bad parts

OMP S2+3 for bad parts

so elim 2 steps for NMP
Ev A(B)€ B E

M: New MP faster but SI
= 2x longer ©

NMP = I bad parts

OMP S2+3 for bad parts

so elim 2 steps for NMP

If defective components can be fixed, that
would add time to the process. If defective
components must be thrown out, that would
also add manufacturing time, because they
would have to make even more. This doesnt
give us two different paths, one of which helps
the conclusion and one of which hurts the
conclusion.

The conclusion focuses on whether the new
process is faster than the old process. Introduc-
ing a third, different process tells us nothing
about the first two processes or how long they
are.

The argument does not address anything
about cost savings — the focus of the argu-
ment's conclusion is solely about saving time.
Whether the company ultimately saves money
does not tell us whether they 11 save time.

9. Genetics: The correct answer is A.

Step 1: Identify the question.

Which of the following is an
assumption on which the argu-
ment depends?

Step 2: Deconstruct the argument.

Two genes, BRCA1 and
BRCA2, are linked to heredi-
tary breast cancer.

ABODE

FA ABODE
Gl and G2 = BC

The word "assumption" indicates
that this is a Find the Assumption
question.

Straight fact.

Assumptions

Therefore, in order to decrease
j the current number of mam-
mogram tests administered
j across a population and to more
accurately zssess a woman's
individual risk of breast cancer,
all women should be tested for
these genes.

Step 3: State the Goal.

FA A B C D E

Gl and G2 = BC

)test all W to I M and assess
risk

Complicated. Okay, the authors
recommending that all women be
tested and claims this will do 2
things: decrease the # of Ms and
better assess risk. So one assump-
tion could be that those who test
negatively wont get an Mas
frequently.

The author claims that, if women are all tested for these genes, two things will happen: the number of Ms will
go down and they'll be able to assess risk more accurately.

I need to find an answer that the author must believe to be true in drawing this conclusion. That might have
something to do with the number of Ms or with assessing risk.

Step 4: Work from wrong to right.

(A) Some of the women
who are tested for the
two genes will sub-
sequently undergo
mammograms on a less
frequent basis than they
used to.

(B) The majority of
breast cancer patients
have no family history
of the disease.

FA A B C D E

Gl and G2 = BC

)test all W to I M and as-
sess risk

FA AfiCDE

Gl and G2 = BC

)test all WtoiM and as-
sess risk

FA AB6DE

Gl and G2 = BC

)test all W to I M and as-
sess risk

If at least some women get tested and then
get fewer Ms, then that would help to reduce
the number of Ms. But does this HAVE to be
true? Actually, I think so. It has to be the case
that women who otherwise would' ve got-
ten Ms don't; otherwise, the number cant go
down.

I'm not sure how this affects the "number of
Ms" claim, but I think it actually hurts the
"better assess risk " claim. It seems like the
argument assumes that if you don't have the
gene, you wont get Ms, but then this choice
says a lot of women who do get BC don't have
a family history. Also, someone can have a
gene and not develop BC, so maybe that's why
there's no family history. Too many "ifs" on
this one.

If so, then presumably the author of the argu-
ment might want to add this third one to
the list. But that has nothing to do with the
argument as it stands.

Chapter 4

Assumptions

(D) Women who have
these genes have an 80
percent chance of get-
ting breast cancer, while
women who do not have
these genes have only

a 10 percent chance of
getting breast cancer.

(E) The presence of
BRCA1 and BRCA2
can explain up to 50
percent of hereditary
cases.

FA A B € B E

Gl and G2 = BC

)test all WtolM and as-
sess risk

FA (A)B € © E

Gl and G2 = BC

)test all W to I M and as-
sess risk

If that's true, then it does sound like knowing
whether you have the gene would help more
accurately assess your risk. Does this HAVE
to be true? Not with those specific numbers,
actually. Tricky. Maybe it's 70 percent or 90
percent instead of 80%; the message is still the
same.

So, of the women who inherit BC, the genes
account for about half of cases. This is kind
of like the last one — that specific number
doesnt have to be true.

MANHATTAN
GMAT

Chapter/5

Critical Reasoning

Strengthen and Weaken

Strengthen and Weaken: The Basics
Strengthen the Conclusion Questions
Weaken the Conclusion Questions

EXCEPT Questions

Strengthen and Weaken

In Chapter 4, we introduced the Assumption Family and discussed Assumption, Evaluate, and Flaw
questions. If you haven't read chapter 4 yet, please do so before reading this chapter; we'll wait!

To recap briefly:

• assumptions are something an author must believe to be true in order to draw his or her
conclusion; these assumptions are NOT stated explicitly in the argument

• all assumption arguments will contain a "core": a conclusion and the major premise or
premises that lead to it

• all assumption arguments will contain at least one (and probably more than one) assump-
tion

In this chapter, we'll address the remaining two Assumption Family question types: Strengthen the
Conclusion and Weaken the Conclusion.

As we saw with the previous three question types, these last two question types also hinge upon identi-
fying an assumption; each has certain characteristics, though, that warrant separating them into these
different categories.

143

5 Strengthen and Weaken
Strengthen and Weaken: The Basics

Both Strengthen and Weaken questions ask us to find a new piece of information that, if added to the
existing argument, will make the conclusion either somewhat more likely to be true (Strengthen) or
somewhat less likely to be true (Weaken). The fact that this information is new, or goes beyond what
we already know from the argument, is the major difference between Strengthen and Weaken questions
and the three question types we examined in the last chapter.

In the case of a Strengthen, the new piece of info will serve as evidence that some assumption is actually
valid. In the case of a Weaken, the new piece of info will knock down some assumption: it will serve as
evidence that the assumption is invalid.

How does that work? Let's look at one of our arguments from the last chapter again, about Thomas's
football team:

Last years 2nd place
team has improved

Team will win CH
this year

(premise) (conclusion

If we were asked an Assumption question, the answer might be something like: Thomas's team has im-
proved enough to be better than the defending champions. In order for the author to draw his conclu-
sion, that must be true. If Thomas's team hasn't improved enough to be better than the first-place team,
then how could we possibly conclude that Thomas's team will win this year?

If we're asked a Strengthen question, how does the answer change? A Strengthen answer provides us
with some new piece of information that does not have to be true, but if true, it does make the conclu-
sion more likely to be valid. For example:

The star quarterback on the defending champion team will miss the game due to
an injury.

Must it be true that the star quarterback will miss the game in order for Thomas's team to win? No. It's
just a new piece of data, one we couldn't have anticipated, but if that information is true, then it also
makes the conclusion more likely to be true. Thomas's team is more likely to win if a star player on the
opposing team can't play.

What happens if we're asked a Weaken question? Similarly, a Weaken answer provides us with some
new piece of information that does not have to be true but, if true, does make the conclusion a bit less
likely to be valid. For example:

The players on the defending champion team train more than the players on any
other team.

MANHATTAN
GMAT

Strengthen and Weaken

That specific fact does not have to be true in order for us to doubt the claim that Thomas's team will
win — there are lots of reasons for us to doubt the claim — but if it is, indeed, true, that the defending
champion team trains more than all the other teams, then the authors conclusion just got weaker.

Note that all Strengthen and Weaken question stems do include the words "if true" or an equivalent
variation. In other words, were explicitly told to accept the possibility that the information in the an-
swer is actually true.

Finally, there are three possible ways that an answer choice could affect the conclusion on both
Strengthen and Weaken questions: the answer strengthens the conclusion, the answer weakens the con-
clusion, or the answer does nothing to the conclusion. As we assess the answers, we'll be keeping these
three categories in mind; we'll label Strengthen answers with an 5, Weaken answers with a W, and
"nothing" answers with an n. We'll discuss this in more detail later.

Strengthen the Conclusion Questions

As we discussed, Strengthen questions ask us to find a new piece of information that, if added to the
existing argument, will make the conclusion somewhat more likely to be true.

Most often, Strengthen questions will contain some form of the words "strengthen" or "support," as
well as the phrase "if true." Here are some typical examples:

Which of the following, if true, most strengthens the argument above?

Which of the following, if true, most strongly supports the mayor's claim?

Strengthen questions will sometimes use synonyms in place of the strengthen / support language; such
synonyms might include:

• provides the best basis or the best reason for

• provides justification for

• provides a piece of evidence in favor of (a plan or a conclusion)

Strengthen questions may occasionally lack the exact phrase "if true" but, if so, some other wording
will provide a similar meaning. That wording might be something quite similar, such as "if feasible."
Alternatively, the wording might indicate that the answer can be "effectively achieved" or "successfully
accomplished" (indicating that the information would become true).

Chapter 5

Strengthen and Weaken

Try out this short example:

At QuestCorp, many employees have quit recently and taken jobs with a competi-
tor. Shortly before the employees quit, QuestCorp lost its largest client Clearly,
the employees were no longer confident in QuestCorp's long-term viability.

Which of the following, if true, most strengthens the claim that concerns about
QuestCorp's viability caused the employees to quit?

(A) Employees at QuestCorp's main competitor recently received a large and
well-publicized raise.

(B) QuestCorp's largest client accounted for 40% of sales and nearly 60% of the
company's profits.

The question stem indicates that this is a strengthen question. Our core might look similar to this:

therefo,

lost client,
ppl quit

(premise)

quit b/c concern
re: success

(conclusion)

Note: you can write the core down as we did above, or you can articulate the core to yourself mentally
(or both!). Whichever path works best for you is fine.

That's interesting. The author claims that, because the company lost its largest client, some employees lost
confidence in the company, so they quit. The author assumes that losing that client will be a significant blow
to the company. What if the company has many clients and the largest client only represented a very small
fraction of the business? The author also assumes there aren't other reasons why employees would have quit.

This is a strengthen question, so I have to find some evidence that actually does support the claim that people
quit specifically because they lost confidence in the company after it lost its largest client.

(A) Employees at Quest-
Corp's main competitor
recently received a large
and well-publicized

raise.

ABC

lost client, ppl quit
©be concern re: success of

com

Wouldn't that make QC's employees jeal-
ous — maybe they'd expect more money?
That'd make it more likely that they quit
because of$ issues rather than a loss of
confidence in the company. If anything, this
actually weakens the conclusion; I want a
strengthen answer.

146

GMAT

Strengthen and Weaken

Chapters

ABC

w s

(B) QuestCorp s largest
client accounted for
40% of sales and nearly
60% of the company's
profits.

(C) Many prospective
hires who have inter-
viewed with QuestCorp
ultimately accepted jobs © bc concern re: success of
with other companies. com

lost client, ppl quit

©be concern re: success of
com

S A®€
lost client, ppl quit

Ouch. Then losing this client would be a
pretty serious blow to the company. This is
a fact that helps make the conclusion a little
more likely; Fll keep it in.

Hmm. "Prospective hires" are not employ-
ees. I was asked to strengthen the part about
employees losing confidence in QC. We could
speculate that maybe something is wrong with
QC if people take other jobs... but the answer
doesnt even tell us why these people took other
jobs. Maybe QC rejected them!

Answer choice A represents one common trap on Strengthen questions: the answer does the opposite of
what we want. That is, it weakens the conclusion rather than strengthening it.

Answer choice C represents another common trap: the answer addresses (and sometimes even strength-
ens) something other than what we were asked to address. In this case, the answer does seem to im-
ply that there's something not so great about QuestCorp, but it discusses the wrong group of people
(prospective hires) and doesnt actually provide any information that allows us to zssess what they think
of QuestCorp's viability. (Again, that last part doesn't matter in the end, because we're already talking
about the wrong group of people in the first place.)

Putting It All Together

Let's try a full problem now.

Donut Chain, wishing to increase the profitability of its new store, will place a
coupon in the local newspaper offering a free donut with a cup of coffee at its
grand opening. Donut Chain calculates that the cost of the advertisement and the
free donuts will be more than recouped by the new business generated through
the promotion.

Which of the following, if true, most strengthens the prediction that Donut
Chain's promotion will increase the new store's profitability?

(A Donut Chain has a loyal following in much of the country.

(B) Donut Chain has found that the vast majority of new visitors to its stores
become regular customers.

(D) Most of the copies of the coupon in the local newspaper will not be re-
deemed for free donuts.

(E) Donut Chain's stores are generally very profitable.

MANHATTAN
GMAT

Strengthen and Weaken

Step 1 ; Identify the question.

Which of the following, if true, S A B C D E
most strengthens the prediction © DC promo _> f prof
that Donut Chain s promotion
will increase the new stores
profitability?

Step 2: Deconstruct the argument.

Donut Chain, wishing to in-
crease the profitability of its new
store, will place a coupon in the
local newspaper offering a free
donut with a cup of coffee at its
grand opening.
Donut Chain calculates that
the cost of the advertisement
and the free donuts will be
more than recouped by the new
business generated through the
promotion.

(brainstorm assumptions)

S A B C D E
©DC promo -» t prof
promo = give free coupon

S A B C D E
©DC promo ^ t prof
promo = give free coupon
$ spent < $ made

S A B C D E
©DC promo -» f prof
promo = give free coupon
$ spent < $ made

Step 3: State the Goal.

The language "if true" and "most
| strengthens the prediction that. . . "
indicates that this is a strengthen
the conclusion question. Also, the
question stem tells me the conclu-
sion I need to address: the plan
will lead to better profitability.

DC thinks that giving away a free
donut will lead to increased profit-
ability.

It costs $ to place the ad and give
away free donuts, but DC thinks it* 11
get enough new business to offset those
costs. Still, does that lead to better
profitability?

The argument isnt 100% clear that
the profitability part is the conclu-
sion, but the question stem also said
so. I can label that info with my ©
symbol. The author is assuming that
giving away a free donut once will
lead to increased revenues over time
(what if they never come back?), and
that will then lead to increase profits
(> revenues dont necessarily equal >
profitability).

I need to strengthen the claim that a particular plan is going to lead to increased profitability. The plan is to
distribute coupons to give away free donuts.

I need to find an answer that makes it a little more likely that this plan will lead to more profits.

Strengthen and Weaken

Chapter 5

Step 4: Work from wrong to right

(A) Donut Chain has a
loyal following in much
of the country.

(B) Donut Chain has
found that the vast ma-
jority of new visitors to
its stores become regular
customers.

(D) Most of the copies
of the coupon in the
local newspaper will not
be redeemed for free
donuts.

(E) Donut Chains
stores are generally very
profitable.

S A B C D E

©DC promo -» t prof

promo = give free coupon

$ spent < $ made
S A B C D E

n S

©DC promo -> T prof

promo = give free coupon

$ spent < $ made
S A B € D E

n S ~~

©DC promo -» t prof

promo = give free coupon

$ spent < $ made
S A B € © E

n S n W

©DC promo t prof

promo = give free coupon

$ spent < $ made
S A B € & E

n S n W ^

©DC promo -> t prof
promo = give free coupon
$ spent < $ made

Common Trap Answers

This is good for DC. Does that mean it will
increase profitability though? No. It's already
an established fact. Plus, it only says that
DC enjoys a loyal following in "much " of the
country, not absolutely everywhere.

So if DC can get people to visit once, they'll
usually keep coming back. That sounds pretty
good for DCs plan, which is all about get-
ting people to visit the first time for that free
donut.

This tells me nothing about profits or reve-
nues or how much they could sell or anything,
really. This doesn't address the conclusion.

If this happens, then DCs plan is really un-
likely to work — it spends money on the ads,
but never gets the new customers to come in.
That weakens the conclusion.

It's good that DC stores are usually profit-
able; that means this new one is likely to be
profitable, too. The claim, though, specifi-
cally asks about increasing the store's profit-
ability — and it specifically asks whether this
plan will accomplish that goal. This choice
looks tempting at first, but it doesn't address
whether this plan will increase profitability.

One of the most common traps is the Reverse Logic answer: the question asks us to strengthen, but a
trap answer choice weakens the conclusion instead. We saw an example of this with answer choice D
in the last problem. These can be especially tricky if we misread the conclusion or otherwise get turned
around while evaluating the argument.

Most of the wrong answers will have No Tie to the Conclusion — they will neither strengthen nor
weaken the conclusion. Some of these will be more obviously wrong, but these answers can also be quite
tricky. A No Tie trap might address something in a premise without actually affecting the conclusion,
for example, as we saw with answer choice E in the last problem.

GMAT

149

Strengthen and Weaken
Takeaways for Strengthen Questions

The question stem will contain "if true" or a close synonym, as well as some form of the word
"strengthen" or "support" (or a synonym). We will write down S to indicate that we have a Strengthen
question.

On Strengthen questions, our goal is to find a new piece of information that makes the conclusion at
least somewhat more likely to be valid.

The most common trap answers include the Reverse Logic trap (weakening the conclusion rather than
strengthening it) and the No Tie trap (doesn't affect the specific conclusion).

Weaken the Conclusion Questions

As we discussed earlier, Weaken questions ask us to find a new piece of information that, if added to
the existing argument, will make the conclusion somewhat less likely to be valid. Our goal, then, is to
attack the conclusion. The correct answer will attack some assumption made by the author.

Most Weaken question stems contain the phrase "if true" (or an equivalent) and question stems similar
to these examples:

• Which of the following, if true, most seriously weakens the conclusion? (variant: which is
a weakness?)

• Which of the following, if true, would cast the most serious doubt on the validity of the
argument? (variant: raise the most serious doubt regarding)

• Which of the following, if true, most strongly calls into question the authors conclusion?

• Which of the following, if true, most seriously undermines the mayors claim?

Sometimes, the question stem will contain more unusual language, such as the words in quotes below:

• find a "disadvantage" or what is "damaging" to the argument

• a plan is "ill-suited" or otherwise unlikely to succeed

• find a "criticism" of the argument

Strengthen and Weaken

Chapter 5

Let s look at the same short example about QuestCorp, but with a different question and answers!

At QuestCorp, many employees have quit recently and taken jobs with a competi-
tor. Shortly before the employees quit, QuestCorp lost its largest client. Clearly,
the employees were no longer confident in QuestCorp's long-term viability.

Which of the following, if true, most seriously undermines the claim that concerns
about QuestCorp's viability caused the employees to quit?

(A) A new competitor in the same town provides health insurance for its em-
ployees, a benefit that QuestCorp lacks.

(B) QuestCorp is unlikely to be able to replace the lost revenue via either an
increase in existing client sales or the attraction of new clients.

The question stem indicates that this is a Weaken question. Our core might look similar to this:

lost client,
ppl quit

(premise)

therefore

quit b/c concern
re: success

(conclusion)

Note: as we discussed on Strengthen question, you can write the core down as we did above, or you can
articulate the core to yourself mentally (or both!). Whichever path works best for you is fine.

Hmm. The author claims that losing this client caused employees to lose confidence in QC, which then caused
them to quit. The author is assuming that losing this one client was serious enough to result in a major prob-
lem for the company; is that necessarily the case? This is a Weaken question, so I have to find some evidence
that makes it less likely that people quit for that reason. That could be because it wasn't really a big problem,
or it could be that there was some other reason that people quit.

ABC

lost client, ppl quit

(A) A new competitor in
the same town provides
I health insurance for its
employees, a benefit that © bc concern re: success of
QuestCorp lacks.

com

The argument claims that people left for one
reason, but this answer actually provides an
alternative. Maybe people quit because they
could get better benefits at the other company.
This would weaken the claim that people quit
specifically because of concerns over QCs vi-
ability as a company.

MANHATTAN
GMAT

151

Strengthen and Weaken

(B) QuestCorp is
unlikely to be able to
replace the lost revenue
via either an increase in
existing client sales or
the attraction of new
clients.

S ABC

w s

lost client, ppl quit

©be concern re: success of
com

S A B €

W S n

lost client, ppl quit

©be concern re: success of
com

So QuestCorp lost its largest client, which
means a loss of revenue, and the company
probably cant find a way to make up that
revenue through other sales. That definitely
reinforces the problem described in the argu-
ment. This actually strengthens the conclu-
sion; that's the opposite of what I want.
Hmm. "Prospective hires" are not employees. I
was asked to weaken the part about employees
losing confidence in QC. We could speculate
that maybe something is wrong with QC
if people take other jobs. . . but the answer
doesnt even tell us why these people took other
jobs. Maybe QC rejected them!

Answer B repeats the common Reverse Logic trap we discussed earlier: it strengthens the conclusion but
we want to weaken the conclusion. Answer C attempts to distract us by talking about a different part
of the argument — perhaps we'll reason that, if interviewees took different jobs, that means they didn't
believe QuestCorp was a good company. We have no idea why these prospective hires ended up work-
ing for another company, though — its entirely possible that QuestCorp didn't extend a job offer to
these people.

Note that we used the exact same answer choice C for both the Strengthen and Weaken versions of this
QuestCorp problem. If a choice is irrelevant to the argument (as choice C was), then it doesn't mat-
ter whether we're asked to strengthen or weaken the conclusion. An irrelevant choice doesn't affect the
conclusion at all.

Strengthen and Weaken

Chapters

Let s try a full example:

The national infrastructure for airport runways and air traffic control requires
immediate expansion to accommodate the increase in private, smaller planes. To
help fund this expansion, the Federal Aviation Authority (FAA) has proposed a fee
for all air travelers. However, this fee would be unfair, as it would impose costs on
all travelers to benefit only the few who utilize the new private planes.

Which of the following, if true, would cast the most doubt on the claim that the
proposed fee would be unfair?

(A) The existing national airport infrastructure benefits all air travelers.

(B) The fee, if imposed, will have a negligible impact on the overall volume of
air travel.

(D) Travelers who use small private planes are almost uniformly wealthy or
traveling on business.

(E) A substantial fee would need to be imposed in order to pay for the expan-
sion costs.

Step 1; Identify the question.

Which of the following, if true,
would cast the most doubt on
the claim that the proposed fee
would be unfair?

W A B C D E
©fee = unfair

The language "cast the most doubt
on the claim" tells me that this is
a weaken question. The specific
claim Fm attacking is that the
proposed fee would be unfair.

Step 2: Deconstruct the argument.

The national infrastructure for
airport runways and air traf-
[ fic control requires immediate
expansion to accommodate
the increase in private, smaller
planes.

To help fund this expansion,
! the Federal Aviation Authority
(EAA) has proposed a fee for all
air travelers.

W A B C D E
©fee = unfair

t sm pi -> must exp infra

W A B C D E
©fee = unfair

t sm pi must exp infra
FAA: fee -» fund exp

This is somewhat claim-like but
it's written as a fact; I'm guessing
its just background info, not the
conclusion, but I'm not 100%
sure.

Okay, here's a plan. It could be
the conclusion. The FAA wants to
charge a fee to pay for the expan-
sion.

MANHATTAN
GMAT

Chapter 5

Strengthen and Weaken

However, this fee would be un-

A B C D E

fair, as it would impose costs on © fce = unfair b/c ^ pay but

all travelers to benefit only the
few who utilize the new private
planes.

few ben

t sm pi -* must exp infra

FAA: fee -» fund exp
W A B C D E

©fee = unfair b/c all pay but
few ben

t sm pi -> must exp infra
FAA: fee fund exp

Change of direction! The author
disagrees with the fee plan, claim-
ing its unfair. Her reasoning is
that everyone would have to pay
the fee, but only a few people
would benefit.

Why wouldn't everyone benefit?
If there's more space, then all the
planes will be able to take off
more quickly. The author is as-
suming the benefit is only for the
people flying in small planes.

Step 3: State the Goal.

The airports are congested because there are so many small planes, and the FAA wants to charge a fee to ex-
pand the airports. The author claims that this is unfair because the fee would be paid by all but the expansion
would only benefit a few.

I want to weaken the authors conclusion, so I need to find some reason why it really isn't unfair. One pos-
sibility that I brainstormed: maybe everyone really will benefit, not just the "small plane" people.

Step 4: Work from wrong to right

(A) The existing nation-
al airport infrastructure
benefits all air travelers.

(B) The fee, if imposed,
will have a negligible
impact on the overall
volume of air travel.

W A B C D E

©fee = unfair b/c all pay but
few ben

T sm pi -» must exp infra

FAA: fee fund exp

W AfiCDE

©fee = unfair b/c all pay but
few ben

t sm pi must exp infra
FAA: fee -» fund exp

This sounds like what I was thinking be-
fore — everyone benefits, so why is it unfair
for everyone to pay? Great; Til leave it in.

A "negligible impact" means it wont really
change anything. The fee wont change the
volume of planes trying to fly. . . but that was
never the plan. The plan was to raise money
to expand the infrastructure — then they'll
be able to handle more volume. This answer
doesn't address the right thing.

MANHATTAN
GMAT

Strengthen and Weaken

Chapter 5

(D) Travelers who use
small private planes
are almost uniformly
wealthy or traveling on
business.

(E) A substantial fee
would need to be im-
posed in order to pay for
the expansion costs.

W ABCDE

w w

©fee = unfair b/c all pay but
few ben

t sm pi -» must exp infra

FAA: fee fund exp

W ABCDE

w w

©fee = unfair b/c all pay but
few ben

t sm pi -» must exp infra
FAA: fee fund exp

W AfiCfiE

w w

©fee = unfair b/c all pay but
few ben

t sm pi ^ must exp infra
FAA: fee -» fund exp

Examine A and C again W AB^BE

©fee = unfair b/c all pay but
few ben

Hmm. This is another potential benefit for
everyone — a reduction in the number of
flight delays. I'll leave this one in, too.

t sm pi must exp infra
FAA: fee -» fund exp

That's nice for them, but what does it have to
do with this argument? Maybe you could say
"so they can afford to pay more," but that isn't
the point of the argument. The point of the
argument is that it's unfair to make the regu-
lar travelers pay for something that doesn't
benefit them (according to the author).
So the fee would have to be pretty large. If
anything, doesn't that make it even more
unfair? Though, actually, Idont think it
really addresses the fairness at all. Either it is
fair, in which case the size of the fee doesn't
matter, or it isn't fair. . . in which case the size
of the fee still doesn't matter.
Okay, I have to compare A and C now.
Both say that this expansion would benefit
everyone... wait a second. C does explicitly
mention the expansion, but A says "the exist-
ing. . . infrastructure. "Existing? Of course the
existing structure benefits everyone who uses
it — the argument isn 't about that. It's about
whether the expansion would benefit every-
one. Only C actually says that; I missed that
the first time around.

Common Trap Answers

Weaken questions contain the same kind of common trap answers that we see on Strengthen questions.

One of the most tricky types is the Reverse Logic trap: the question asks us to weaken, but a trap an-
swer choice strengthens the conclusion instead. We will also again see the No Tie traps — choices that
might discuss something in a premise but don't affect the conclusion.

Our most tempting wrong answer in the last problem, answer choice A, is actually a No Tie trap. It was
so tempting specifically because almost everything in the choice was addressing the right thing but one
word made it wrong: "existing." The conclusion was about the future infrastructure, after an expansion, so

MANHATTAN
GMAT

Chapter 5

Strengthen and Weaken

limiting the answer to the existing infrastructure meant that the information didn't affect the conclu-
sion after all.

Takeaways for Weaken Questions

The question stem will contain "if true" or a close synonym, as well as some form of the words "weak-
en," "doubt," "undermine," or a synonym. We will write down "W" to indicate that we have a Weaken
question.

On Weaken questions, our goal is to attack the conclusion. The correct answer will be a new piece of
information that makes the conclusion at least somewhat less likely to be valid.

The most common trap answers include the Reverse Logic trap (strengthening the conclusion rather
than weakening it) and the No Tie trap (doesn't affect the specific conclusion).

EXCEPT Questions

Assumption Family questions may also be presented in a "negative" form that is commonly referred to
as Except questions.

A regular Weaken question might read:

Which of the following, if true, most seriously weakens the conclusion?
An Except Weaken question might read:

Each of the following, if true, weakens the conclusion EXCEPT:

What is the difference in wording between those two questions?

The first one tells us that one answer choice, and only one, weakens the conclusion. That is the answer
choice that we want to pick.

The second one tells us that four answer choices weaken the conclusion. These four are all wrong an-
swers. What about the fifth answer — what does that one do?

Many people will assume that the fifth one must do the opposite: strengthen the conclusion. This is
not necessarily true. Rather, the fifth one cannot weaken the conclusion but it may not strengthen the
conclusion either. It might have no impact whatsoever on the conclusion.

For these negatively-worded questions, were going to use the "odd one out" strategy. Four of the an-
swers will do the same thing; in the case of the above example, four answers will weaken the conclusion.
The fifth answer will do something else. It doesn't matter whether the fifth one strengthens the conclu-
sion or does nothing — all that matters is that it is the "odd one out."

GMAT

Strengthen and Weaken

The four answers that do the same thing can be found by using the regular strategy that we would use
for that question type. On a normal Weaken question, we want to choose the answer that makes the
conclusion at least a little less valid. On an EXCEPT Weaken question, four answer choices will make
the conclusion at least a little less valid, and we are going to cross those four choices off. The remaining
answer will be the answer we pick.

Here's a full example.

Supporters of a costly new Defense Advanced Research Projects Agency (DARPA)
initiative assert that the project will benefit industrial companies as well as the
military itself. In many instances, military research has resulted in technologies
that have fueled corporate development and growth, and this pattern can be
expected to continue.

Each of the following, if true, serves to weaken the argument above EXCEPT:

(A) The research initiative will occupy many talented scientists, many of whom
would otherwise have worked for private corporations.

(B) In the past decade, DARPA has adopted an increasingly restrictive stance
regarding the use of intellectual property resulting from its research.

(C) If the DARPA initiative hadn't been approved, much of the funding would
instead have been directed toward tax breaks for various businesses.

(D) At any given time, DARPA is conducting a wide variety of costly research
projects.

(E) The research initiative is focused on defense mechanisms that will reduce
injury to soldiers during combat, a need that is nonexistent for private cor-
porations.

Strengthen and Weaken

Step 1: Identify the question.

Each of the following, if true,
serves to weaken the argument
above EXCEPT:

WEx

A B C D E

The language "serves to weaken*
tells me that this is a weaken
question. The word EXCEPT tells
me that the 4 wrong answers will
weaken and I want to pick the
"odd one out" answer.

Step 2: Deconstruct the argument

Supporters of a costly new
Defense Advanced Research
Projects Agency (DARPA) ini-
tiative assert that the project will
benefit industrial companies as
well as the military itself.
In many instances, military re-
search has resulted in technolo- ^
gies that have fueled corporate
development and growth, and
this pattern can be expected to
continue.

WEx A B C D E
SD: ben ind corns & mil

WEx A B C D E

)SD: ben ind corns & mil

past: mil res -» techs to help
corns, will com

The SDs (Supporters of DARPA)
think that this really costly project
will be good for companies and
the military.

Research has helped corns in the
past, and the author claims this
will keep happening in the future.
That all supports the claim of the
SDs: that the specific D project
will be beneficial for corns.

Step 3: State the Goal

In the past, military research has helped companies, and the claim is that this D project will also help compa-

nies.

I want to find four answers that weaken the conclusion (make it at least a little less likely to be valid). The
answer that doesnt weaken — the odd one out — is the correct answer.

Step 4; Work from wrong to right.

(A) The research initia-
tive will occupy many
talented scientists, many
of whom would other-
wise have worked for
private corporations.

A B C D E

WEx

)SD: ben ind corns & mil

past: mil res -» techs to
help corns, will cont

This benefits the military and specifically does
not benefit the companies. That does weaken
the idea that companies will benefit.

Strengthen and Weaken

Chapters

(B) In the past decade,
DARPA has adopted an
increasingly restrictive
stance regarding the use
of intellectual prop-
erty resulting from its
research.

(C) If the DARPA
initiative hadn't been
approved, much of the
funding would instead
have been directed
toward tax breaks for
various businesses-
CD) At any given time,
DARPA is conducting
a wide variety of costly
research projects.

(E) The research initia-
tive is focused on de-
fense mechanisms that
will reduce injury to
soldiers during combat,
a need that is nonexis-
tent for private corpora-
tions.

Examine B and D again

WEx A B C D E

w w?

)SD: ben ind corns & mil

past: mil res -» techs to
help corns, will cont

WEx A B € D E

w w? w

)SD: ben ind corns & mil

past: mil res techs to
help corns, will cont

WEx A B € D E

W W? W n

©SD: ben ind corns & mil

past: mil res -» techs to
help corns, will cont

WEx A B € D E

WW? W n W

©SD: ben ind corns & mil

past: mil res -» techs to
help corns, will cont

WEx AB€@E

W W? Wn W

)SD: ben ind corns & mil

past: mil res techs to
help corns, will cont

Hmm. "Restrictive" makes it sound like D
doesn't let others use its research as much. If
that's the case, then that would weaken the
idea that companies will benefit. I'm not to-
tally sure that's what this means though — the
wording is tricky — so I'm not going to cross
this one off yet.

A tax break is a good thing, This choice is say-
ing that the funding for the D project would
instead have been spent on tax breaks, which
is a definite benefit. So not giving those tax
breaks is a bad thing for the companies; this
does weaken the argument.

This choice talks about all research projects D
is conducting. Hmm. The argument makes
a claim only about one specific project. Does
this information make that claim more or
less likely to be valid? I can't really see how it
affects the argument's conclusion at all.
The key here is the language "a need that is
nonexistent for private corporations. " If the
private companies don't have any need for the
results of this particular research, then that
weakens the claim that the D research will
benefit companies.

I need to compare B and D. I thought B
might weaken a little bit, and I thought D
didn't do anything to the conclusion. Between
those two, I should choose the one that doesn't
weaken at all, so I'm going to choose D.

The biggest "trap answer" on an EXCEPT question is simply to forget halfway through that were
working on an EXCEPT question. In other words, halfway through the above question, if I forget that
it's a Weaken EXCEPT, I might accidentally pick a Weaken answer, or pick the answer that I think
most weakens the conclusion.

MANHATTAN
GMAT

159

Chapter 5

"1"

Strengthen and Weaken
Takeaways for EXCEPT Questions

Any of the five Assumption Family question types can be worded as an EXCEPT question. When that
happens, the four wrong answers will be formulated in whatever way a right answer would have been
written on a normally-worded question of that type. That is:

On EXCEPT
questions

Wrong answers will

Right answers will

Assumption

be an assumption on which the
argument depends

NOT be an assumption on
which the argument depends

Evaluate

help to tell us whether the conclu-
sion may be valid

NOT help to tell us whether
the conclusion may be valid

Flaw

represent a flaw in the reasoning

NOT represent a flaw in the
reasoning

Strengthen

strengthen the conclusion at least
a little

NOT strengthen the conclu-
sion

Weaken

weaken the conclusion at least a
little

NOT weaken the conclusion

On EXCEPT questions, we remind ourselves first what the usual goal is for a normal question of that
type. The four wrong answers will follow that typical goal, and the right answer will be the "odd one
out" — it will NOT do what we typically expect on a normal question of that type.

When writing down the question type, add the designation "Ex" to whatever you normally write down
for that question type.

MANHATTAN
GMAT

Strengthen and Weaken

Problem Set

Chapters

1. Digital Video Recorders

Advertising Executive: More than 10 million households now own digital video
recorders that can fast-forward over television commercials; approximately 75%
of these households fast-forward over at least one commercial per 30-minute
program. Because television commercials are not as widely watched as they used
to be, they are much less cost-effective today.

Which of the following, if true, strengthens the claim that television commercials
are less cost-effective than they used to be?

(A) Product placement within television programs is a viable alternative to tradi-
tional television commercials.

(B) The television programs preferred by consumers without digital video re-
corders are similar to those preferred by consumers with the devices.

(C) Prior to the advent of digital video recorders, very few television viewers
switched channels or left the room when commercials began.

(D) The cost-effectiveness of television advertising is based less upon how many
people watch a particular commercial and more upon the appropriateness
of the demographic.

(E) Many companies find it difficult to determine the exact return on invest-
ment for television commercials.

2. Smithtown Theatre

The Smithtown Theatre, which stages old plays, has announced an expansion that
will double its capacity along with its operating costs. The theatre is only slightly
profitable at present. In addition, all of the current customers live in Smithtown,
and the population of the town is not expected to increase in the next several
years. Thus, the expansion of the Smithtown Theatre will prove unprofitable.

Which of the following, if true, would most seriously weaken the argument?

(A) A large movie chain plans to open a new multiplex location in Smithtown
later this year.

(B) Concession sales in the Smithtown Theatre comprise a substantial propor-
tion of the theatre's revenues.

(C) Many recent arrivals to Smithtown are students that are less likely to attend
the Smithtown Theatre than are older residents.

(D) The expansion would allow the Smithtown Theatre to stage larger, more
popular shows that will attract customers from neighboring towns.

(E) The Board of the Smithtown Theatre often solicits input from residents of
the town when choosing which shows to stage.

MANHATTAN
GMAT

Chapters

Strengthen and Weaken

3. Books and Coffee

The owners of a book store and a nearby coffee shop have decided to combine
their businesses. Both owners believe that this merger will increase the number
of customers and therefore the gross revenue, because customers who come for
one reason may also decide to purchase something else.

Which of the following, if true, most weakens the owners' conclusion that a
merger will increase revenue?

Books and drinks can both be considered impulse purchases; often, they are
purchased by customers without forethought.

Profit margins at a coffee shop are generally significantly higher than profit
margins at a book store.

People who are able to read the first chapter of a book before buying are
more likely to decide to buy the book.

A large majority of the book store's current customer base already frequents
the coffee shop.

A combination book store and coffee shop that opened in a neighboring
city last year has already earned higher than expected profits.

4. Digital Coupons

The redemption rate for e-mailed coupons is far lower than that for traditionally
distributed paper coupons. One factor is the "digital divide"— those who might
benefit the most from using coupons, such as homemakers, the elderly, and those
in low-income households, often do not have the knowledge or equipment nec-
essary to go online and receive coupons.

Which of the following, if true, does the most to support the claim that the digital
divide is responsible for lower electronic coupon redemption rates?

(A) Computers are available for free in libraries, schools, and community centers.

(B) The redemption rate of ordinary coupons is particularly high among elderly
and low income people that do not know how to use computers.

(D) More homemakers than elderly people would use computers if they had ac-
cess to them.

(E) The redemption rate for coupons found on the internet has risen in the last
five years.

MANHATTAN
GK/1AT

Strengthen and Weaken

5. Teacher Compensation

Traditionally, public school instructors have been compensated according to
seniority. Recently, educational experts have criticized the system as one that
rewards lackadaisical teaching and reduces motivation to excel. Instead, these
experts argue that, to retain exceptional teachers and maintain quality instruc-
tion, teachers should receive salaries or bonuses based on performance rather
than seniority.

Which of the following, if true, most weakens the argument of the educational
experts?

(A) Some teachers express that financial compensation is not the only factor
contributing to job satisfaction and teaching performance.

(B) School districts will develop their own unique compensation structures that
may differ greatly from those of other school districts.

(C) Upon leaving the teaching profession, many young, effective teachers cite a
lack of opportunity for more rapid financial advancement as a primary factor
in the decision to change careers.

(D) In school districts that have implemented pay for performance compensa-
tion structures, standardized test scores have dramatically increased.

(E) A merit-based system that bases compensation on teacher performance
reduces collaboration, which is an integral component of quality instruction.

6. The Gold Standard

Brand X designs and builds custom sneakers, one sneaker at a time. It recently an-
nounced plans to sell "The Gold Standard," a sneaker that will cost five times more
to manufacture than any other sneaker that has ever been created.

Which of the following, if it occurred, would cast the most serious doubt on the
claim that The Gold Standard sneaker will be profitable?

(A) The endorsement of The Gold Standard by a popular celebrity

(B) The publication of a report indicating that all previous sneaker lines
launched by Brand X have been profitable

(D) The introduction of another new sneaker line by a rival manufacturer

(E) An announcement by Brand X that The Gold Standard will be marketed as
an exclusive offering, available only in limited quantities

Chapters

Strengthen and Weaken

7. Machu Picchu

In 2001 the Peruvian government began requiring tourists to buy permits to hike
the Inca Trail to the ancient city of Machu Picchu. Only 500 people per day are
now allowed to hike the Inca Trail, whereas before 2001 daily visitors numbered in
the thousands. The Peruvian government claims that this permit program has suc-
cessfully prevented deterioration of archaeological treasures along the Inca Trail.

Which of the following, if true, most strengthens the argument above?

Since 2001, Incan ruins similar to Machu Picchu but without a visitor limit
have disintegrated at a significantly greater rate than those on the Inca Trail.
Villages near Machu Picchu have experienced declines in income, as fewer
tourists buy fewer craft goods and refreshments.

Many of the funds from the sale of Inca Trail permits are used to hire guards
for archaeological sites without permit programs.
Since 2001, tourist guides along the Inca Trail have received 50% to 100%
increases in take-home pay.

The total number of tourists in Peru has risen substantially since 2001, even
as the number of tourists hiking the Inca Trail has remained constant.

Ethanol, a fuel derived from corn, can be used alone to power cars or along with
gasoline to reduce the reduce the amount of gas consumed. Unlike gasoline,
ethanol is easily renewable since it is primarily converted from the sun's energy.
Moreover, compared with conventional gasoline, pure ethanol is a cleaner-
burning fuel. To save energy and reduce pollution, many individuals advocate the
increased usage of ethanol as a primary fuel source in conjunction with or in place
of gasoline.

In evaluating the recommendation to increase the use of ethanol, it would be
important to research all of the following EXCEPT:

(A) Whether the energy required to grow and process corn used as fuel is
greater than the amount of energy ultimately produced

(B) Whether more energy is saved when using ethanol in conjunction with or in
place of gasoline

(D) Whether it is possible to produce more ethanol than is currently produced

(E) Whether the process of growing corn for fuel would result in as much pollu-
tion as does the production of conventional gasoline

(A)
(B)
(C)

8. Ethanol

MANHATTAN
GMAT

Strengthen and Weaken

Chapter 5

CEO: Over the past several years, we have more than doubled our revenues but
profits have steadily declined because an increasing number of customers have
failed to pay their balances. In order to compensate for these higher default rates,
we will increase the interest charged on outstanding balances from an annual
percentage rate (APR) of 9.5% to an APR of 12%. This increase will be sufficient to
compensate for the current rate of defaults and allow us to increase our profits.

Which of the following statements, if true, would most seriously undermine a plan
to increase interest rates in order to spur profitable growth?

(A) Many other companies have experienced a similar trend in their default
rates.

(B) The company's operating expenses are above the industry average and can
be substantially reduced, thus increasing margins.

(C) The increase in default rates was due to a rise in unemployment, but unem-
ployment rates are expected to drop in the coming months.

(D) The proposed increase in the APR will, alone, more than double the com-
pany's profit margins.

(E) An increase in the APR charged on credit card balances often results in
higher rates of default.

MANHATTAN
GMAT

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10. Jupiter vs. Mars

Scientists suspect that Europa, a moon orbiting Jupiter, may contain living organ-
isms. However, the government recently scrapped an unmanned science mission
to Europa and replaced it with a project aimed at landing an astronaut on Mars.
Polls show that the public is far more fascinated by space travel than by discover-
ing life elsewhere in the universe. Critics argue that the government's decision-
making process places a greater emphasis on popularity than it does on the
importance of scientific research.

Which of the following, if true, would most strengthen a contention by the gov-
ernment that the new project is a better use of its funds?

(A) In the first year of the project, the government will spend 30% of its total

(C) Some scientists are convinced that a mission to Europa would add immea-
surably to our understanding of the universe.

(D) A new telescope that has just become available to scientists promises to
yield more information than the planned mission to Europa was designed to
provide.

(E) Most people feel that a shuttle to Mars is the next logical step in the devel-
opment of a system that will allow humans to travel even further in the solar
system.

(B)

budget on developing a space shuttle that can travel to Mars; that figure is
expected to drop to 0% after five years.

The government cannot be absolutely certain of the chances for success of
either project.

166

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Chapters

Solutions

1. Digital Video Recorders: The correct answer is C.
Step 1: Identify the question.

Which of the following, if S A B C D E

true, strengthens the claim that /^w w C r

I V comm < cost err now

television commercials are less
cost-effective than they used to
be?

Step 2: Deconstruct the argument.

Advertising Executive: More
than 10 million households now
own digital video recorders that
can fast-forward over television
commercials;

approximately 75% of these
households fast-forward over
at least one commercial per
30-minute program.

Because television commercials
are not as widely watched as
they used to be, they are much
less cost-effective today.

S A B C D E
©TV comm < cost eff now
AE: 10m hh = DVR

S A B C D E

©TV comm < cost eff now

AE: 10m hh = DVR

75% FF comms (#)
S A B C D E

©TV comm < cost eff now b/c
ppl watch <

AE: 10mhh = DVR

75% FF comms (#)

Step 3: State the Goal.

The phrase "strengthens the
claim" tells me that this is a
Strengthen question. The question
stem also tells me the conclusion:
TV commercials are less cost-
effective than they used to be. Til
write that down.

This is just a fact.

Another fact. I don't think I need
to write down the exact numeri-
cal details right now, but I'll note
that there are more numerical
details just to remind myself

This repeats the conclusion I
already know from the Qstem,
with a little more info.

Okay, theAE claims that TV comms are not as cost-effective specifically because people aren't watching them
as much, and that is specifically because most people fast-forward over at least some commercials. What as-
sumptions are being made?

Let's see. They're assuming that people really did watch TV commercials more, but they don't provide any evi-
dence of that. Maybe people used to tape programs on VCRs and then still fast-forward. They haven't actually
told us what people used to do before these DVRs came along.

MANHATTAN
GMAT

Chapter 5

Strengthen and Weaken

/ want an answer that will make the claim a little more likely to be valid.
Step 4: Work from wrong to rig ht.

(A) Product place-
ment within television
programs is a viable
alternative to traditional
television commercials.

(B) The television
programs preferred
by consumers without
digital video record-
ers are similar to those
preferred by consumers
with the devices.

(C) Prior to the advent
of digital video record-
ers, very few televi-
sion viewers switched
channels or left the
room when commercials
began.

(D) The cost-effec-
tiveness of television
advertising is based less
upon how many people
watch a particular com-
mercial and more upon
the appropriateness of
the demographic.

(E) Many companies
find it difficult to deter-
mine the exact return
on investment for televi-
sion commercials.

S A B C D E

©TV comm < cost eff now
b/c ppl watch <

AE: 10m hh = DVR

75% FF comms (#)
S AfiCDE

©TV comm < cost eff now
b/c ppl watch <

AE: 10m hh = DVR

75% FF comms (#)

S ABCDE

©TV comm < cost eff now
b/c ppl watch <

AE: 10m hh = DVR

75% FF comms (#)

S AfiCBE

s w

©TV comm < cost eff now
b/c ppl watch <

AE: 10m hh = DVR

75% FF comms (#)

S AB©BE

5 w w

©TV comm < cost eff now
b/c ppl watch <

AE: 10mhh = DVR

75% FF comms (#)

That's nice for the advertisers who want to
make money, but it's not talking about how
to do so by NOT using commercials, so that
cant affect the conclusion about whether TV
commercials are less cost-effective now.

Hmm. The DVR thing was used as evidence
to show how some people are skipping com-
mercials. I don't think making a distinction
about people with or without the DVRs
watch really tells us anything. The conclusion
is about commercials, not what programs
people watch.

That's interesting. This is about what people
used to do before DVRs. Oh, look — I didn't
think of that, but they mention two other
ways that people could skip commercials:
changing the channel or leaving the room.
And this answer says that people really didn't
used to do that, so maybe they really were
watching more TV commercials!
Hmm. They're saying that we should be using
a different metric to evaluate cost-effective-
ness, not how many people watch. Yeah, that
sounds convincing. Wait! My goal is to find
something that makes the argument MORE
likely to be valid. If anything, this would
weaken the argument; this is a Reverse Logic
trap!

A lot of companies can't tell how much money
they earn from people watching TV commer-
cials. But maybe they can still tell something
about the relative differences between a few
years ago and now. Also, if this were actually
true, if anything, the conclusion would be a
little less valid, because that would mean we
couldn't tell that the TV commercials are less
cost-effective today.

168

GMAT

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Chapters

2. Smithtown Theatre: The correct answer is D.

Step 1: Identify the question.

Which of the following, if true,
would most seriously weaken
the argument?

Step 2: Deconstruct the argument.

The Smithtown Theatre, which
stages old plays, has announced
an expansion that will double its
capacity along with its operating
costs.

The theatre is only slightly prof-
itable at present.

In addition, all of the current
customers live in Smithtown,
and the population of the town
is not expected to increase in the
next several years.
Thus, the expansion of the
Smithtown Theatre will prove
unprofitable.

Step 3: State the Goal.

A B C D E

W A B C D E
ST: exp to tt cap & cost

W ABODE

ST: exp to tt cap & cost

Now: barely prof
W A B C D E

ST: exp to tt cap & cost

Now: barely prof, cust live in
S, prob won't be more from S

W A B C D E

ST: exp to tt cap & cost

Now: barely prof, cust live in
S, prob wont be more from S

)ST exp unprof

The words "if true" and "weaken"
tell me that this is a Weaken ques-
tion.

They have a plan. It's future, so
it could be the conclusion, but
I'm guessing there'll be more of a
claim like "The ST will (or will
not) be successful with its plan" or
something like that.
This is a fact. I wonder: if ST
expands, will it get enough new
business to continue covering costs?

The first half is a fact; the second
half is a future predication. So
far, the case for ST's new plan
doesn't sound very good.

Okay, here's the conclusion. The
author thinks the plan will fail
and provides some pieces of evi-
dence to support that claim.

The ST has a plan to expand but the author claims that the plan will fail because the ST is only barely profit-
able right now and it doesn't seem like there are a lot more opportunities to get new customers.

I want something that will weaken the author's claim. I have to be careful here: weaken the idea that
the plan will fail. I'm not weakening the plan itself — in fact, weakening the author's claim might mean
strengthening the idea that the plan will work!

Mil

'■mm

MANHATTAN
GMAT

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Chapters

Strengthen and Weaken

Step 4: Work from wrong to right.

(A) A large movie chain
plans to open a new
multiplex location in
Smithtown later this
year.

(B) Concession sales in
the Smithtown Theatre
comprise a substantial
proportion of the the-
atre's revenues.

(C) Many recent arrivals
to Smithtown are stu-
dents that are less likely
to attend the Smithtown
Theatre than are older
residents.

(D) The expansion
would allow the Smith-
town Theatre to stage
larger, more popular
shows that will attract
patrons from neighbor-
ing towns.

(E) The Board of the
Smithtown Theatre
often solicits input from
residents of the town
when choosing which
shows to stage.

A B C D E

ST: exp to tt cap & cost

Now: barely prof, cust live
in S, prob wont be more
from S

©ST exp unprof

W A B C D E

S n

ST: exp to tt cap & cost

Now: barely prof, cust live
in S, prob won't be more
from S

©ST exp unprof
W A B € D E

S n S

ST: exp to tt cap & cost

Now: barely prof, cust live
in S, prob won't be more
from S

)ST exp unprof
W A B € D E

S n S W

ST: exp to tt cap & cost

Now: barely prof, cust live
in S, prob won't be more
from S

)ST exp unprof
W AB€@E

ST: exp to tt cap & cost

Now: barely prof, cust live
in S, prob won't be more
from S

Idont think what another business does will
matter. If anything, you d have to say that
the new movie theatre would take business
from ST, which would strengthen the authors
claim that ST will fail.

How would this change if ST expanded? That
still depends upon whether they can get more
people to come to the theatre, so this doesnt
really tell me anything new.

So the new people moving to town are people
who arent likely to start going to ST. That
strengthens the authors claim that STs ex-
pansion is going to fail. Reverse Logic trap!

Hmm. This basically means that the expan-
sion would attract a greater audience — that
helps! If they have more people, they can fill
the larger theatre and make more money.
This one is looking good.

This is how they do things now. Would it stay
the same, or change when they expand? I have
no idea. This doesnt tell me that some new
thing will happen that might make it more
likely for the plan to succeed; it just talks
about how things are already done.

)ST exp unprof

170

GMAT

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Chapters

3. Books and Coffee: The correct answer is D.

Step 1; Identify the question.

| Which of the following, if
true, most weakens the owners'
conclusion that a merger will

! increase revenue?

Step 2: Deconstruct the argument.

The owners of a book store

W A B C D E
) merger -» T rev

A B C D E

and a nearby coffee shop have © merger f fey (B + Q
decided to combine their busi-

nesses.

Both owners believe that this
merger will increase the number
of customers and therefore the
gross revenue,

because customers who come for
one reason may also decide to
purchase something else.

W A B C D E
) merger t rev(B + C)

W A B C D E

)B + C merger -» t cust -» T
rev

Cust of each will buy >

Step 3: State the Goal.

The words "if true" and "weak-
ens" tell me that this is a Weaken
question. Further, I now know
the conclusion: some merger will
result in increased revenue.

This is a fact; they have already
made this decision, although it
sounds like they haven't actually
mergedyet.

Here's the conclusion. This is the
same thing the Q_ stem said: the
merger will increase revenue.

Okay, so I need to rewrite because
they just inserted another step
in the middle. The individual
customers of each store will end
up buying both books and coffee,
so there'll be more customers for
both, which means more rev-
enue for both. That's assuming,
of course, that these customers
weren't already going to both
stores to buy stuff.

The owners think that merging will lead to increased revenue because it'll increase the number of customers
and the customers will buy more stuff. This assumes that the same customers weren't already going to both
stores and buying stuff.

This is a Weaken question so I need to find something that will make the conclusion less likely to be valid.

GMAT

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Chapters

Strengthen and Weaken

Step 4: Work from wron g to rig ht.

(A) Books and drinks
can both be considered
impulse purchases; of-
ten, they are purchased
by customers without
forethought.

(B) B Profit margins at a
coffee shop are generally
significantly higher than
profit margins at a book
store.

(D) A large majority of
the book stores current
customer base already
frequents the coffee
shop.

(E) A combination book
store and coffee shop
that opened in a neigh-
boring city last year has
already earned higher
than expected profits.

A B C D E

)B + C merger -» t cust
t rev

Cust of each will buy >

W AfiCDE

S n

)B + C merger -» t cust -»
t rev

Cust of each will buy >
W A fi € D E

S n S

)B + C merger t cust -»
T rev

Cust of each will buy >
W AfiCDE

S n S W

)B + C merger t cust -*
t rev

Cust of each will buy >

W Afi€®£

S n S TP n

)B + C merger -» t cust -»
t rev

Cust of each will buy >

j This could be a reason why people would buy

more. If they normally just buy coffee but
I see a book they like, maybe they'll be more
i likely to buy. That would strengthen the plan
to merge, but I want to weaken the plan.
Reverse Logic trap!

1 That might make the coffee shop owner not
want to merge, but it doesn't address the
revenue side of the equation at all — and
the conclusion has to do with revenues, not
profits.

\ This helps the owners' argument again! If I
can sit there and read while having my coffee,
| then I'm more likely to buy the book, which
j would increase revenues.

\ Let's see. Most of the people who shop at the
book store also already go to the coffee shop.
\ That's not so good for the owner's plan — it
i means that they're not going to pick up
i as many new customers as we might have
thought before.

Two problems here. One, we're not talking
j about the same book store and coffee shop.
\ Two, this choice talks about profits, not

revenues.

4. Digital Coupons: The correct answer is B.
Step 1: Identify the question.

Which of the following, if true,
does the most to support the
claim that the digital divide is
responsible for the lower usage
of electronic coupons?

S A B C D E
©DD -> I use e-coup

| The language <( if true" and "sup-
port the claim" tell me that this
\ is a Strengthen question. The
) question also indicates the conclu-
| sion: something called the "digital
j divide" causes electronic coupons
1 not to be used as much.

172

GMAT

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Chapters

Step 2: Deconstruct the argument.

The redemption rate for e-
mailed coupons is far lower than
that for traditionally distributed
paper coupons.
One factor is the "digital di-
vide" — those who might benefit
the most from using coupons,
such as homemakers, the elderly,
and those in low-income house-
holds, often do not have the
knowledge or equipment neces-
sary to go online and receive
coupons.

Step 3: State the Goal.

S A B C D E
)DD -» I use e-coup
e-C ii use than PC
S A B C D E

)DD -» I use e-coup
e-C ii use than PC

This is a fact. For some reason,
e-mailed coupons don t get used as
much as paper coupons.

Okay, so the people who would
typically use Cs are less likely to
be able to get them electronical-
ly — they have to use the paper Cs
DD: ppl who use Cs cant get instead. This doesn't really articu-
them online ^ ate ^ e conclusion that well — the

question stem did, so I'm going to
add something here

The author claims that the "digital divide" (DD) causes lower use of the e-coupons because people who use
coupons aren't as likely to have access to e-coupons.

I need to find something that makes this a little more likely to be true.

Step 4: Work from wrong to right.

(A) Computers are avail-
able for free in libraries,
schools, and community
centers.

(B) The redemption rate
of ordinary coupons is
particularly high among
elderly and low income
people that do not know
how to use computers.

S A B C D E

©DD -* I use e-coup

e-C i i use than PC

DD: ppl who use Cs can't
get them online

S A B C D E

w s

DD I use e-coup

e-C 1 1 use than PC

DD: ppl who use Cs cant
get them online

If this is true, then people who don't have
computers can still use them. Maybe they
could even take classes to learn how to use
them! If anything, this weakens the author's
claim.

At first glance, I thought, "This is just saying
what the argument already said, which is
weird because usually they don't do that. "
Then I realized that there was a gap in the
argument! The argument only says that these
people without computers are the ones who
would "benefit the most" from coupons, but
it doesn't say that these people actually do use
coupons more. This choice tells me that; this
strengthens the conclusion.

GMAT

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Chapter 5

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(D) More homemak-
ers than elderly people
would use computers if
they had access to them.

(E) The redemption rate
for coupons found on
the internet has risen in
the last five years.

A B € D E

W S n

DD -> I use e-coup

e-C H use than PC

DD: ppl who use Cs can t
get them online
S A B € B E

W S n n

©DD -* I use e-coup

e-C H use than PC

DD: ppl who use Cs cant
get them online
1 S A®€ & E

DD -» I use e-coup

e-C ii use than PC

DD: ppl who use Cs cant
get them online

The argument doesn 't say that people have to
have high-speed connections in order to get
coupons. The issue was whether these groups
had internet access at all, not how fast the
internet access is.

The argument doesn V make any distinction
between homemakers and the elderly; rather,
they re both equally part of the group of people I
without easy access to the internet. This is
irrelevant.

This means that more people are using
electronic coupons today, but the argument
doesn t claim that people arent. Instead, it
talks about the fact that paper coupons are
still in wider use because some people find it
harder to access the electronic coupons. This
answer does nothing to affect the conclusion.

5. Teacher Compensation: The correct answer is E.
Step 1: Identify the question.

Which of the following, if true,
most weakens the argument of
the educational experts ?

A B C D E

The language "if true" and
"weakens" tells me this is a
Weaken question. In addition,
the question tells me that I need
to look for a reference to "educa-
tional experts" because whatever
they claim is the conclusion.

Step 2: Deconstruct the argument.

Traditionally, public school
instructors have been compen-
sated according to seniority.
Recently, educational experts
have criticized the system as
one that rewards lackadaisical
teaching and reduces motivation
to excel.

W A B C D E
Old: PST comp by sen.

W ABCDE
Old: PST comp by sen.
EE: i> motiv

Fact. Teachers were getting paid
based upon how long they've
worked.

I guess the EEs are implying that
teachers dont have to feel moti-
vated to work hard because they
know they'll make more money
regardless.

174

GMAT

Strengthen and Weaken

Chapters

w A b c D E

Old: PST comp by sen.

EE: 4 motiv

)EE: base comp on perf
keep good Ts, good instr.

So the EEs want to base com-
pensation on performance, and
they claim this will lead to better
teachers and instruction.

Instead, these experts argue
that, to retain exceptional
teachers and maintain qual-
ity instruction, teachers should
receive salaries or bonuses based
on performance rather than
seniority.

Step 3: State the Goal.

Teachers normally get paid based on seniority, but the EEs want them to be paid based on performance be-
cause they say that the teachers will then be better.

I need to find something that weakens this plan at least a little bit.

Step 4: Work from wron g to rig ht.

(A) Some teachers
express that financial
compensation is not the
only factor contributing
to job satisfaction and
teaching performance.

(B) School districts
will develop their own
unique compensation
structures that may dif-
fer greatly from those of
other school districts.

(C) Upon leaving the
teaching profession,
many young, effective
teachers cite a lack of
opportunity for more
rapid financial advance-
ment as a primary
factor in the decision to
change careers.

W A B C D E

Old: PST comp by sen.

EE: 4 motiv

©EE: base comp on perf
keep good Ts, good instr.

W A B C D E

n n

Old: PST comp by sen.

EE: I motiv

©EE: base comp on perf
keep good Ts, good instr.
W A B € D E

n n S

Old: PST comp by sen.

EE: I motiv

©EE: base comp on perf
keep good Ts, good instr.

So maybe we should also consider other ways
to reward good teachers too, but as long as
financial compensation is a factor, then tying
compensation to performance might be a good
plan. According to this answer, financial
compensation is a factor (though not the only
one).

The argument isn't claiming that every school
district has to be identical. It just makes a
recommendation that compensation be tied to
performance in general.

If anything, I think this would strengthen
the EEs claim! It shows that teachers do care
about the financial side of things and causes
some good teachers to leave the profession at a
young age.

MANHATTAN 175
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Chapters

Strengthen and Weaken

(D) In school districts
that have implemented
pay for performance
compensation struc-
tures, standardized test
scores have dramatically
increased.

(E) A merit-based sys-
tem that bases com-
pensation on teacher
performance reduces
collaboration, which is
an integral component
of quality instruction.

W A B € & E

n n S S

Old: PST comp by sen.

EE: I motiv

©EE: base comp on perf -»
keep good Ts, good instr.

W A B € ©

n n S S

Old: PST comp by sen.

EE: I motiv

©EE: base comp on perf
keep good Ts, good instr.

Again, if anything, this makes the EEs' plan
sound better. Students in the school districts
that have already followed the EEs' recom-
mendation are doing better on tests!

The EE plan has a drawback: it reduces
something that is considered an <( integral
component" of good teaching If that's true, it
could hurt the idea that basing compensation
on performance will result in maintaining
good instruction.

6. The Gold Standard: The correct answer is C.

Step 1: Identify the question.

Which of the following, if it
occurred, would cast the most
serious doubt on the claim that
The Gold Standard sneaker will
be profitable ?

W A B C D E
©TGS will be prof

Step 2: Deconstruct the argument.

Brand X designs and builds W A B C D E

custom sneakers, one sneaker at ^ will be prof
a time.

It recently announced plans
to sell "The Gold Standard," a
sneaker that will cost five times
more to manufacture than any
other sneaker that has ever been
created.

W A B C D E

©TGS will be prof

will sell TGS, 5x more to
make

This one is a little unusual.
Instead of "if true, " it says "if it
occurred " — but that's a synonym
of "if true." This language, in ad-
dition to "serious doubt," indicates
that this is a Weaken question.
Further, the claim is that TGS
will be profitable.

This is just a fact. I'm not even
sure I need to write it down — it's
just telling me what kind of com-
pany Brand X is.
It costs five times as much to
make? Wow. And yet the claim is
that they'll be profitable. There
are a LOT of assumptions going
on here.

MANHATTAN
GMAT

Strengthen and Weaken

Chapters

Step 3: State the Goal.

The claim is that TGS will be profitable and the only piece of "evidence" says that the sneakers are ridiculous-
ly expensive to make. So there's no real evidence to support the idea that these will be profitable! Profitability
is based on revenues minus costs, so the author is assuming that they can sell the sneakers for even more than it
costs to make them.

I'm looking for an answer that makes the conclusion less likely to be true.
Step 4: Work from wrong to right.

(A) The endorsement of W A B C D E
The Gold Standard by a © TGS J { be prof
popular celebrity

will sell TGS, 5x more to

make
W

AfiCDE

s s

(B) The publication of a
report indicating that all q tg$ ^ ^ prof
previous sneaker lines
launched by Brand X
have been profitable

will sell TGS, 5x more to
make

(D) The introduction
of another new sneaker
line by a rival manufac-
turer

AfiCDE

s s w

©TGS will be prof

will sell TGS, 5x more to
make

©TGS will be prof

AfiCBE

S S W n

will sell TGS, 5x more to
make

Endorsements usually help companies sell
more of a product, so this would help the
claim that TGS will be profitable. Reverse
logic!

Really, I think this has nothing to do with
the given conclusion; there's no reason why
TGS must be profitable just because other
Brand X sneakers were profitable — especially
because TGS sneakers cost so much to make.
If anything, this answer makes it more likely
that TGS will be profitable, too.
Lets imagine that TGS is profitable when
the costs are five times higher. This choice is
saying that the costs are going to go up even
more . Profits equal revenues minus costs, so
increasing the per-product cost makes it less
likely that the product can be profitable.
This one is so tempting! If another sneaker be-
comes popular, perhaps the sales of TGS will
drop. That doesn't necessarily affect whether
TGS will be profitable, though. Again, profits
equal revenues minus costs. But if you make
fewer sneakers, then costs will go down as
well — so its not necessarily the case that
reducing revenues will also impact the level of
profitability.

MANHATTAN
GMAT

Chapters

Strengthen and Weaken

(E) An announcement
by Brand X that The
Gold Standard will be
marketed as an exclusive
offering, available only
in limited quantities

W A B ©B E

S S W n n

©TGS will be prof

will sell TGS, 5x more to
make

This doesn't seem to tell me much one way
I or the other. If anything, I think you could
speculate that an "exclusive" product could
| sell for a premium price, so maybe that would
1 make it more likely that TGS will be profit-
able.

7. Machu Picchu: The correct answer is A.
Step 1: Identify the question.

Which of the following, if true, S
most strengthens the argument
above ?

Step 2: Deconstruct the argument.

In 2001 the Peruvian govern-
ment began requiring tourists
to buy permits to hike the Inca
Trail to the ancient city of Ma-
chu Picchu.

Only 500 people per day are
now allowed to hike the Inca
Trail, whereas before 2001
daily visitors numbered in the
thousands.

The Peruvian government
claims that this permit pro-
gram has successfully prevented
deterioration of archaeological
treasures along the Inca Trail. (

Step 3: State the Goal.

A B C D E

I The words "if true" and
j "strengthens the argument"
j indicate that this is a Strengthen
1 question.

S A B C D E
01 PG: perm to hike IT

S A B C D E
01 PG: perm to hike IT
now: 500 ppl / d (old = 000 s)

This is a fact. People now have to
pay to hike the Inca Trail.

| More facts. Now, only 500 people
a day can go; before, there were
thousands a day.

S A B C D E
01 PG: perm to hike IT

Here's the claim: the PG specifi-
cally says that the permit program
j is responsible for preventing
now: 500 ppl / d (old = 000 s) | deterioration.

)PG: perm -» A deter of IT

The PG claims that its permit program has been responsible for preventing deterioration along the IT. The
only thing we know about the permit program is that it has reduced the number of people who can visit the
IT. So the government is assuming that reducing the number of visitors was the cause, and that if the permit
program hadnt been in place, then there would have been deterioration.

I need to find something that makes this a little more likely to be valid.

MANHATTAN
GMAT

Strengthen and Weaken

Chapter 5

Step 4: Work from wrong to right.

S A B C D E

(A) Since 2001, Incan
ruins similar to Machu
Picchu but without a
visitor limit have disin-
tegrated at a significant-
ly greater rate than those © PG: perm _> j, deter of IT
on the Inca Trail.

(B) Villages near Machu
Picchu have experienced
declines in income, as
fewer tourists buy fewer
craft goods and refresh-
ments.

01 PG: perm to hike IT

now: 500 ppl / d (old =
000's)

S AfiCDE

S n

01 PG: perm to hike IT

now: 500 ppl / d (old =
000's)

(C) Many of the funds
from the sale of Inca
Trail permits are used to
hire guards for archaeo-
logical sites without
permit programs.

(D) Since 2001, tourist
guides along the Inca
Trail have received 50%
to 100% increases in
take-home pay.

(E) The total number of
tourists in Peru has risen
substantially since 2001,
even as the number

of tourists hiking the
Inca Trail has remained
constant.

)PG: perm -» I deter of IT
S A B € D E

S n n

01 PG: perm to hike IT

now: 500 ppl / d (old =
000s)

)PG: perm I deter of IT
S A fi € B E

S n n n

01 PG: perm to hike IT

now: 500 ppl / d (old =
000's)

)PG: perm-> 4- deter of IT
S ®B € © £

;5 n n n n

01 PG: perm to hike IT

now: 500 ppl / d (old =
000's)

)PG: perm-» I deter of IT

This sounds promising. The government s
assumption was that the visitor limit helped
prevent deterioration, so showing that other
sites without limits did experience deterio-
ration would make it more likely that the
governments reasoning is valid. V 11 definitely
keep this one in.

This sounds bad for the villages, but it doesnt
impact the specific claim about preventing
deterioration along the IT

This sounds like a good use of funds, but it
has nothing to do with whether the permit
program really did help prevent deterioration.
All this tells us is that maybe other sites are
also better protected due to the guards.

Thats great for the guides. It doesnt impact
the actual conclusion at all, though.

This ones about the number of visitors again,
so maybe it strengthens. Lets see. A lot more
people are visiting Peru. . . oh, but the second
part is what we were already told: visitors to
the IT are limited. This doesnt add anything
new that specifically affects the claim about
deterioration along the IT

8. Ethanol: The correct answer is B.

Did this one seem a little different from all of the others? We set a trap for you! This is an Evaluate
question, not a Strengthen or a Weaken. We discussed Evaluate questions in the previous chapter. (And
we did warn you at the beginning of this chapter to read the last chapter first!)

On the real test, you'll never have the luxury of knowing that the next question will be a certain
type — so be prepared for anything

MANHATTAN
GMAT

Chapter 5

Strengthen and Weaken

Step 1: Identify the question.

In evaluating the recommen-
dation to increase the use of
ethanol, it would be important
to research all of the following
EXCEPT :

EvEx

A B C D E

Step 2: Deconstruct the argument.

Ethanol, a fuel derived from
corn, can be used alone to pow-
er cars or along with gasoline to
reduce the reduce the amount of
gas consumed.

Unlike gasoline, ethanol is easily
renewable since it is primarily
converted from the sun s energy.

Moreover, compared with con-
ventional gasoline, pure ethanol
is a cleaner-burning fuel.

To save energy and reduce pollu-
tion, many individuals advocate
the increased usage of ethanol
as a primary fuel source in
conjunction with or in place of
gasoline.

Step 3: State the Goal.

EvEx A B C D E
E: fuel, use alone or w/gas
4 use of FF

EvEx A B C D E

E: fuel, use alone or w/gas

I use of FF

easy to get > E

EvEx A B C D E

E: fuel, use alone or w/gas

I use of FF

easy to get > E, clean burn
EvEx A B C D E

E: fuel, use alone or w/gas

4 use of FF

easy to get > E, clean burn
)use E -> save NRG, I poll

The word "evaluating" (the
conclusion) tells me that this is
an Evaluate question. Its also an
Except question. The four wrong
ones WILL be important to evalu-
ate; the correct answer will NOT
be important to evaluate. The
conclusion will have something to
do with using ethanol.

All facts. This E stuff is a kind of
fuel, and it can be used in cars,
either alone or with gas.

Interesting. It's easier to get more
ethanol than more gasoline.

And ethanol is "cleaner-burning. "
This E stuff sounds pretty good so
far.

Conclusion! People think that us-
ing E will save NRG and reduce
pollution. (Note: NRG is an ab-
breviation for energy.)

The E fuel has various good qualities, so people say we should use it and we'll save energy and reduce pollu-
tion.

On regular Evaluate questions, we try to find an answer that will tell us whether the conclusion is more or
less valid. The answer can take us down two "paths," one of which will make the conclusion a bit better and

MANHATTAN
GMAT

Strengthen and Weaken

Chapter 5

the other of which will make it a bit worse. On this EXCEPT question, all four wrong answers will do this.
I'm looking for the "odd one out" that does NOT do this.

Step 4: Work from wrong to right.

(A) Whether the energy-
required to grow and
process corn used as
fuel is greater than the
amount of energy ulti-
mately produced

(B) Whether more
energy is saved when us-
ing ethanol in conjunc-
tion with or in place of
gasoline

EvEx A B C D E
E: fuel, use alone or w/gas
I use of FF

easy to get > E, clean burn
©use E ^ save NRG, I poll

EvEx A B C D E
E: fuel, use alone or w/gas
I use of FF

easy to get > E, clean burn
©use E -> save NRG, i poll

EvEx A B € D E
E: fuel, use alone or w/gas
I use of FF

easy to get > E, clean burn
)use E -» save NRG, I poll

(D) Whether it is pos-
sible to produce more
ethanol than is currently
produced

EvEx AB6BE
E: fuel, use alone or w/gas
i use of FF

easy to get > E, clean burn
)use E -» save NRG, I poll

The conclusion specifically claims that we'll
save energy. If the amount of energy to pro-
duce ethanol is MORE than the amount of
energy produced, then we ar en t saving ener-
gy. If the amount of energy to produce ethanol
is LESS than the amount of energy produced,
then we are saving energy. This answer gives
me "two paths" so it's wrong (since I want the
EXCEPT answer).

This answer choice uses many of the same
words as the conclusion. But that's a trap!
The conclusion makes no distinction between
these two methods of using ethanol; it just
recommends in general that we do use etha-
nol. If more energy is saved using ethanol in
conjunction with gasoline, then the conclusion
holds. If more energy is saved using ethanol
in place of gasoline, then the conclusion holds.
Either way, it's the same thing! There aren't
"two paths" here.

If ethanol is as efficient as or more efficient
than gasoline, then we could use less ethanol
to get the same amount of power. That would
save energy, making the conclusion a bit
stronger. If ethanol is less efficient than gas,
then we would have to use more ethanol to get
the same amount of power. That might mean
it takes more energy for the car to go the same
distance, making the conclusion weaker. We
have "two paths" here.
The conclusion says we should "increase" the
usage of ethanol. But is more ethanol avail-
able to use? If we can produce more ethanol,
then that makes the argument a bit stronger.
If we cannot produce any more ethanol, then
how can we increase the usage? That would
make the argument weaker.

MANHATTAN
GMAT

181

er 5

Strengthen and Weaken

(E) Whether the process
of growing corn for fuel
would result in as much
pollution as does the
production of conven-
tional gasoline

EvEx A(B)€ B £
E: fuel, use alone or w/gas
I use of FF

easy to get > E, clean burn
)use E -> save NRG, I poll

The conclusion claims that using ethanol will
reduce pollution, but the argument tells us
only that ethanol burns more cleanly than
gas. If the process of making ethanol results
in less pollution, this would be another point
in favor of the conclusion. If the process of
making ethanol results in more pollution than
does the production of gasoline, however, then
this would weaken the conclusion.

9. APR: The correct answer is E.
Step 1: Identify the question.

Which of the following state-
ments, if true, would most
seriously undermine a plan to
increase interest rates in order to
spur profitable growth?

Step 2: Deconstruct the argument.

CEO: Over the past sev-
eral years, we have more than
doubled our revenues but profits
have steadily declined because
an increasing number of cus-
tomers have failed to pay their
balances.

In order to compensate for these
higher default rates, we will
increase the interest charged on
outstanding balances from an
annual percentage rate (APR) of
9.5% to an APR of 12%.

W A B C D E
) t int rate -» t prof growth

W ABODE

C: 2x rev but l prof b/c cust
not pay bills

W ABODE

C: 2x rev but I prof b/c cust
not pay bills

t % to comp

The "if true" and "undermine"
language indicate that this is a
Weaken question. Further, the
question stem tells me the conclu-
sion: there's a plan to increase
interest rates and that is then sup-
posed to cause profits to grow.

Several facts here. Revenues have
gone up but profits have gone
down because the customers aren't
paying what they owe.

Okay, here's the plan. They'll
charge more interest to everyone
to compensate for the people who
aren't paying their bills.

MANHATTAN
GMAT

Strengthen and Weaken

This increase will be sufficient
to compensate for the current
j rate of defaults and allow us to
increase our profits.

W A B C D E Hmm. They're claiming that 12%

. _^ ^ r i will be enough to compensate for

T int rate -» T prof growth & r j

the current rate of people who
C: 2x rev but I prof b/c cust don't pay so that they can increase
not pay bills profits (which is the conclusion I

T % to comp; 12% is suff for already wrote down). They're as-
now default suming that the current rate isn't

going to get worse in future.

Step 3: State the Goal.

The company plans to charge higher interest rates in order to become profitable again. The evidence shows
only that the higher interest rate will be sufficient for today's default rate; that could change over time.

This is a Weaken question so I need to find something that makes the CEO's conclusion a bit less likely to be
valid.

Step 4: Work from wrong to right.

(A) Many other compa-
nies have experienced
a similar trend in their
default rates.

A B C D E

(B) The company's
operating expenses
are above the industry
average and can be sub-
stantially reduced, thus
increasing profits.

C: 2x rev but 4 prof b/c
cust not pay bills

t % to comp; 12% is suff

for now default

W ABCDE

n n

C: 2x rev but I prof b/c
cust not pay bills

t % to comp; 12% is suff
for now default

This doesn't address the company's plan to fix
the problem: increasing the interest rate. This
doesn't impact the conclusion at all.

Hmm. If the company does this, it could in-
crease profits, which is the company's goal. . .
but the conclusion is that the plan to increase
interest rates will improve profits, and this
choice doesn't address that plan. Plus, if any-
thing, this choice makes it more likely that the
company will increase profits, but we want to
weaken the conclusion.

Chapter 5

Strengthen and Weaken

(C) The increase in
default rates was due to
a rise in unemployment,
but unemployment rates
are expected to drop in
the coming months.

(D) The proposed in-
crease in the APR will,
alone, more than double
the company's profit
margins.

(E) An increase in the
APR charged on credit
card balances often
results in higher rates of
default.

W A fi € D E

n n n

) t int rate -» t prof
growth

C: 2x rev but I prof b/c
cust not pay bills

t % to comp; 12% is suff

for now default

W A fi € B E

n n n S

) t int rate -* t prof
growth

C: 2x rev but 4 prof b/c
cust not pay bills

t % to comp; 12% is suff
for now default
W A fi € B

n n n S

) t int rate t prof
growth

C: 2x rev but 4 prof b/c
cust not pay bills

t % to comp; 12% is suff
for now default

10. Jupiter vs. Mars: The correct answer is D.
Step 1: Identify the question.

| If unemployment caused people not to pay
| their bills, and fewer people are going to be
j unemployed, then maybe more will pay their
bills? That would help the company, but we
want something that will weaken the conclu-
sion. And the conclusion is specifically about
the plan. This choice doesnt address the
specific plan about interest rates.

This supports the company s claim that
increasing the interest rate will help raise
| profits. I want something that weakens that
claim.

Okay, if they do increase the APR, then more
people may stop paying their bills as a result!
The conclusion specifically said that raising
the APR would compensate for the "current
rate of defaults," so if the rate goes up, then
the company is less likely to increase its profits.
This does weaken the conclusion.

Which of the following, if true,
would most strengthen a con-
tention by the government that
the new project is a better use of
its funds?

S A B C D E
)G: new proj = better

j The words "if true" and

I "strengthen a contention" indicate
that this is a Strengthen question.
Further, the question stem tells
me the conclusion: the government \
claims that the new project is a
better use of funds.

MANHATTAN
GMAT

Strengthen and Weaken

Step 2: Deconstruct the argument.

Scientists suspect that Europa,
a moon orbiting Jupiter, may
contain living organisms.

However, the government
recently scrapped an unmanned
science mission to Europa and
replaced it with a project aimed
at landing an astronaut on
Mars.

Polls show that the public is far
more fascinated by space travel
than by discovering life else-
where in the universe.

Critics argue that the govern-
ment s decision-making process
places a greater emphasis on
popularity than it does on the
importance of scientific re-
search.

S A B C D E
) G: new proj = better
S: E may have life
S A B C D E

)G: new proj = better

S: E may have life

cncl E project, rplc w/M
project

S A B C D E

)G: new proj = better

S: E may have life

cncl E project, rplc w/M
project

ppl like spc trvl >
S A B C D E

) G: new proj = better

S: E may have life

cncl E project, rplc w/M
project

ppl like spc trvl

C: govt cares popul > rsrch

There is a fact: scientists sus-
pect something is true. We dorit
actually know whether its true,
though.

There was a project to send an
unmanned mission to E, but that
was replaced by another project to
send a person to Mars. More facts.

More facts — a survey showed that
people like space travel more.

This is a counter-conclusion. The
critics say that the government is
just paying attention to popular-
ity of projects, but the question
stem told me that the government
claims that the new project is a
better use of funds.

Step 3: State the Goal.

There are two opposing points of view, the government and the critics. The government claims that the new
project is a better use of funds. The critics claim that the government is paying more attention to popularity
than to scientific research. The critics are assuming that, just because the public finds the Mars project more
interesting, there arent also good scientific reasons for replacing the Europa project with the Mars project.

I need to strengthen the government s claim. I need to be really careful that I don t mistakenly strengthen the
critics* claim.

Strengthen and Weaken

Step 4: Work from wrong to rig ht.

(A) In the first year of
the project, the govern-
ment will spend 30%
of its total budget on de-
veloping a space shuttle
that can travel to Mars;
that figure is expected
to drop to 0% after five
years.

(B) The government
cannot be absolutely
certain of the chances
for success of either
project.

(C) Some scientists are
convinced that a mis-
sion to Europa would
add immeasurably to
our understanding of
the universe.

(D) A new telescope
that has just become
available to scientists
promises to yield more
information than the
planned mission to
Europa was designed to
provide.

S A B C D E

^)G: new proj = better

S: E may have life

cncl E project, rplc w/M
project

ppl like spc trvl

C: govt cares popul >
rsrch

S ABC D E

n n

©G: new proj = better

S: E may have life

cncl E project, rplc w/M
project

ppl like spc trvl

C: govt cares popul >
rsrch

t S A B € D E

n n W

©G : new proj = better

S: E may have life

cncl E project, rplc w/M
project

ppl like spc trvl

C: govt cares popul >
rsrch

S A B € D E

n n W S

©G: new proj = better

S: E may have life

cncl E project, rplc w/M
project

ppl like spc trvl

C: govt cares popul >
rsrch

This doesn't give us any additional informa-
tion as to why the Mars project is better than
the Europa project. We don t know whether
i they'd be spending more or less on the E
project, nor do we know what kind of good
research they'll expect to get in return.

Was there anything in the argument that

hinged on being absolutely certain of success?
| No. If they told us that the Mars project has

a greater chance for success, that would be
\ good — but knowing that we don't know the

chances for either project. . . that doesn't add

anything.

This is a good reason to continue funding the
mission to E. But that would support the crit-
ics, not the government. This is a trap.

Now they have a new telescope that they can
use to get even more research than they would
have if they sent an unmanned mission?
That's a good reason to cancel the unmanned
mission. If that's true, then pretty much any
other decent project would be a better use of
funds!

Strengthen and Weaken

Chapter 5

(E) Most people feel
that a shuttle to Mars
is the next logical step
in the development of
a system that will allow
humans to travel even
further in the solar
system.

S A fi €® £

)G: new proj = better

S: E may have life

cncl E project, rplc w/M
project

ppl like spc trvl

C: govt cares popul >
rsrch

That's interesting, but it doesn't tell us
anything new about why spending the money
on the Mars project is better than spending
money on the Europa project. We already
know that people are more interested in space
travel. This answer is a tangent that's trying
to get us to think more about that and make
us forget about the conclusion, which centered
on a comparison of the two projects.

MANHATTAN
GMAT

Chapter

Critical Reasoning

Evidence Family

-pm

C/f BBS

What Are Inferences?
Percentages vs. Real Numbers
Inference Questions
Explain a Discrepancy
EXCEPT Questions

Evidence Family

The Evidence Family of questions is our third main family. Here's a recap of what we discussed in
Chapter 2:

• No Conclusions! These are made up entirely of premises

• No Assumptions either!

• Two main question types: Inference and Explain a Discrepancy

Inference questions require us to find an answer that must be true according to the premises given in the
argument.

Explain a Discrepancy questions require us to identify some kind of paradox or puzzling result in an
argument and find an answer that explains, or resolves, the puzzling part of the argument. Before we
delve further into each type, let's talk about what inferences are in general.

What Are Inferences?

In order to answer inference questions accurately, we first need to understand what the GMAT test
writers mean when they ask us to infer something. In the GMAT World, an inference is something that
must be true according to the evidence given in the argument. In the Real World, by contrast, we don't
think of inferences in this way; rather, in the Real World, inferences are likely to be true based on the
available evidence, but they dont absolutely have to be true.

For example, if a friend tells you that chocolate is her favorite flavor of ice cream, what kind of real-
world inferences might you make?

You might infer that she likes chocolate in general and that she likes ice cream in general. Maybe she
likes all desserts in general — perhaps she has a sweet tooth. All of these things are perfectly reasonable
to infer in a "likely to be true" situation, but not a single one has to be true. Its possible that she really

191

Evidence Family

likes chocolate only when it's in the form of ice cream, and she really likes ice cream only when its
chocolate. The kinds of answers discussed in this paragraph would be tempting incorrect answers on the
GMAT.

What does have to be true? She can't like vanilla ice cream better than she likes chocolate ice cream — if
chocolate is her favorite flavor of ice cream, then by definition she doesn't like any other flavor better.
She has to have tried at least one other flavor of ice cream at some point in her life — she has to have
had the ability to compare with at least one other flavor in order to decide that chocolate is her favorite
flavor. These kinds of answers would be correct answers on the GMAT.

From now on, when we discuss how to infer something, we'll be referring to the GMAT's definition:
something that must be true based on the available evidence.

Percentages vs. Real Numbers

Let's say that we're discussing a company that sells only vanilla and chocolate ice cream. We're told
that 55% of the company's profits last year were derived from chocolate ice cream sales and 40% of the
revenues last year were derived from vanilla ice cream sales. What can we infer?

Because we know that the company sells only these two products, we can figure out two additional
numbers. If 55% of profits came from chocolate, then 45% of profits came from vanilla. If 40% of
revenues came from vanilla, then 60% of revenues came from chocolate. These things must be true, but
these inferences are probably too easy for any GMAT question. What else can we infer?

The company earned 60% of its revenues, but only 55% of its profits, from chocolate. By contrast, the
company earned 40% of its revenues and a higher percentage of its profits, 45%, from vanilla. That's
interesting. We made more money on vanilla than we would have expected based on the percentage of
revenues, and we made less money on chocolate than we would have expected based on the revenues.
Profitability is a measure of profits versus revenues. The vanilla ice cream product is more profitable
than the chocolate ice cream product. That must be true.

What doesn't have to be true? It doesn't have to be true that vanilla will continue to be more profitable
in the future. The trend might not continue in the future.

Let's say there are two ice cream companies, X and Y. Chocolate ice cream represents 60% of Company
X s sales and 50% of Company Y's sales. Clearly, then, Company Y sells more chocolate ice cream,
right?

Not necessarily. We have no information about real numbers here, only percentages, and we don't even
know how those percentages relate to each other. What if company Y has $1 million in annual revenues
and company X has only $10,000 in annual revenues? We can't conclude anything about actual dollar
amounts from this information about percentages.

Evidence Family

Inference Questions

Chapter 6

Inference questions require us to find an answer that must be true according to the information in the
argument. Most of the time, we will need to use only some of the information in the argument, though
we may use all of it.

Most Inference question stems contain some form of the word "conclude" or some form of the word
"infer," though there are some variations that don't include those specific words. Examples of words or
phrases contained in Inference questions include:

• which answer can be " logically concluded" or the "statements above most strongly
support which of the following conclusions"?

• which answer can be "properly inferred"?

• the statements above "best support" which of the following "assertions"?

• which answer "must be true" based upon the above statements?

Note that Inference question stems can contain the language "most strongly support." We also saw this
language on Strengthen questions, so it is critical to ensure that we don't mix up the two question types.

The below diagram shows the "direction" of the support. On Inference questions, the argument (above)
is used to support the correct answer (below). On Strengthen questions, the correct answer (below) is
used to support the conclusion of the argument (above):

Argument

Strengthen

Strongly
Supports

Answers

Inference

Inference questions ask us to use the argument to support an answer (the answer concludes some-
thing from the argument). By contrast, Strengthen questions ask us to use an answer to support the

argument (strengthen the argument / conclusion). Strengthen questions will contain a conclusion in
the argument or question stem; Inference arguments will not contain a conclusion in the argument or
question stem.

MANHATTAN
GMAT

Chapter 6

Evidence Family

Let's take a look at a short example.

Both enrollment and total tuition revenue at Brownsville University have in-
creased during each of the last four years. During the same period, enrollment
at Canterbury University has steadily decreased, while total tuition revenue has
remained constant.

Which of the following hypotheses is best supported by the statement given?

(A) Brownsville University now collects more total tuition revenue than does
Canterbury University.

(B) The per-student tuition at Canterbury University has risen over the last four
years.

The question stem is one of the slightly different variations. It uses the word "hypotheses" instead of
"conclusions," but it means the same thing: an inference question. Our core might look like this:

Note that, on all inference questions, the right-hand side of the core will always look like the above.
We'll only be given premises.

4 yrs:
BU: enrol, tuit t
CU: enrol I, tuit =
(premise)

therefore

[what must be true?]

(inference)

Hmm. There are two schools but different trends are happening. BUs enrollment and tuition revenues are
both going up. CUs enrollment is going down, but tuition revenues are the same.

This is an Inference question, so I have to find an answer that must be true according to my premises.

(A) Brownsville University
now collects more total tuition
revenue than does Canterbury
University.

4 yrs:

BU: enrol, tuit T

ABC

Things have certainly been looking up
for BU lately, but I know absolutely
nothing about the actual dollar values
that the schools are collecting. It's en-

CU: enrol i>, tuit =

tirely possible that CU still collects more
money than BU.

MANHATTAN
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Evidence Family

Chapter 6

(B) The per-student tuition at
Canterbury University has risen
over the last four years.

4 yrs:

ABC

Let's see. "Per-student tuition' '= rev-
enues I # of students. CU has the same
revenues today, so the numerator stays
the same, but fewer students, so the

BU: enrol, tuit t

CU: enrol 4, tuit =

denominator gets smaller. Dividing by
a smaller number = a larger number.
This must be true! Til check C, butFm
feeling good about this one.

In A(B)€

4 yrs:

This might be reasonable to believe in
the real world, but it doesnt have to
be true. A trend never absolutely has to
continue in the future.

BU: enrol, tuit t

CU: enrol I, tuit =

The argument provides us with several fact-based premises. (It is also possible to have premises that are
somewhat more claim-based.) The correct answer is something that must be true based on those prem-
ises, though note that, in this case, we only needed to use the information about Canterbury in order to
draw the correct conclusion. Answer B didn't use the Brownsville data at all.

Answer A tried to trap us by getting us to make a conclusion based on information we don't have (ac-
tual dollar values). Answer C is a classic "real-world inference" trap — it might be reasonable to believe
that the trend will continue, but nothing says that a trend must continue in the future.

Let's try a full example; set your timer for 2 minutes:

Curbing government spending has been demonstrated to raise the value of a
country's currency over time. However, many economists no longer recommend
this policy. A currency of lesser value causes a country's exports to be more com-
petitive in the international market, encouraging domestic industries and making
the economy more attractive to foreign investment.

The statements above most strongly support which of the following inferences?

(A) Limited government spending can also lead to a reduction in the national
deficit.

(B) Curbing government spending can make a country's exports less competi-
tive.

(D) An increase in the value of a currency will result in reduced government
spending.

(E) Competitive exports indicate a weak currency.

MANHATTAN
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Evidence Family

Step 1 : Identify the question.

The statements above most
strongly support which of the
following inferences?

Step 2: Deconstruct the argument

A B C D E

; They re asking me to support
something below (in the answers), \
and they use the word "inference. " j
This is an Inference question.

Curbing government spending
has been demonstrated to raise
the value of a country's currency
over time.

However, many economists no
longer recommend this policy.

A currency of lesser value causes
a country's exports to be more
competitive in the international
market, encouraging domes-
tic industries and making the
economy more attractive to
foreign investment.

In A B C D E
1 gov sp -» t val curr

In A B C D E
I gov sp -* t val curr
BUT E don't rec

In A B C D E

I gov sp -* T val curr

BUTE don't rec

I val curr -> exp > comp
benefits

This is a fact. Fairly straight-
forward — one thing leads to
another.

Hmm. According to the first
sentence, raising the value of cur-
rency sounds like a good thing, so
why wouldn't the Es want us to

j do that?
Oh, okay, so there are some good
reasons to have a lower currency
value. I guess those economists

\ think these benefits outweigh the

j lower value.

Step 3: State the Goal.

Reducing government spending will increase currency value. It seems like it would be good to have a high
currency value, but some Es say that we shouldn't do that, because there are other benefits involved in having
a lower currency value.

I need to find an answer that must be true given the information in the argument. I don't need to use all of
the info in the argument, though I may.

Step 4: Work from wrong to right.

(A) Limited government In A B C D E

spending can also lead
to a reduction in the
national deficit.

i gov sp t val curr

BUT E don't rec

4 val curr exp > comp
-> benefits

Deficit? This might be reasonable to believe
in the real world, but there was nothing
! about the deficit in the argument — I don't
have any evidence to support this statement.

Evidence Family

(B) Curbing government
spending can make a
country's exports less
competitive.

(D) An increase in the
value of a currency will
result in reduced gov-
ernment spending.

(E) Competitive exports
indicate a weak cur-
rency.

In ABCDE

4 gov sp -» t val curr

BUT E don't rec

4 val curr -» exp > comp
-> benefits

In ABCDE

4 gov sp -» t val curr

BUT E dont rec

4 val curr exp > comp
benefits

In A B C B E

4 gov sp 1 s val curr

BUT E don t rec

4 val curr -» exp > comp
-» benefits

In A B € & E

4 gov sp t val curr

BUT E don't rec

4 val curr exp > comp
-» benefits

Z^i see. The author said that curbing spend-
ing leads to a higher currency value. And
then the Es said that a lower currency value
makes exports more competitive. If that's true,
then a higher currency value could make ex-
ports less competitive. . . so, hey, it is actually
the case that curbing spending might lead to
less-competitive exports! Keep this one in.
The argument says "many economists," and
the answer says "many economists," so that
part is okay. If you tell someone not to lower
their spending, is that the same thing as
telling them to increase their spending? No.
You could also recommend spending the same
amount. Tricky! This one isn't a "must be
true" statement.

This one feels similar to B — language pretty
similar to the argument, and I have to figure
out what leads to what. The author said that
X (curbing spending) will lead to Y(a higher
currency value). This answer reverses the
direction: Ywill lead to X. That's not what
the author said!

The Es said that M (a lower currency value)
leads to N (more competitive exports). The
answer reverses the direction but changes the
description a bit: N indicates that M is true
or has happened. IfM leads to N, then isn't it
the case that having N could indicate that M
happened? Yes. Leave this one in.

Now I need to compare B and E. I checked the logic on B and E, and they both seem good — in both cases,
the causal direction could be true. Let me check the wording of the answers to make sure I'm reading them
correctly. Oh, I see. B says that curbing spending "can make" exports less competitive, which is true, while E
says that competitive exports "indicate" a weak currency. Answer E is missing the "can" or "could" part. It
might be the case that competitive exports indicate a weak currency, but the argument never says that this is
definitely the case.

The correct answer is B.

er 6

Evidence Family

Common Trap Answers

The most tempting wrong answers on Inference questions tend to revolve around making Real World
Inferences — things that we would reasonably assume to be true in the real world but don't absolutely
have to be true. Some of these wrong answers may go way too far and be quite obviously out of scope,
but the trickiest ones will seem very reasonable. . . until we ask ourselves whether that answer MUST be
true.

Answer choice E in our last problem did this, and so did answer choice C. The argument said merely
that economists "no longer recommend" a policy to reduce spending. The trap answer said that the
economists recommend higher spending. Many people in the real world might assume or infer this, but
it doesn't have to be true! There's also a third option: maintaining the same level of spending.

Other wrong answers will use language very similar to the language in the argument but will Reverse
Direction or Switch Terms somehow. If we're told that eating honey causes people to hiccup, then a
wrong answer might say that hiccupping causes people to eat honey! Alternatively, if we're told that the
flu causes higher temperatures, then a wrong answer might say that the flu causes a fever. Higher tem-
peratures and fevers are not interchangeable, but may seem to be if you're not reading carefully. Term
switching is only acceptable if both terms are synonyms.

Takeaways for Inference Questions

Most of the time, inference questions will contain some form of the word "conclude" or "infer," though
other variations are possible. Common synonyms include "assertion" or "hypothesis" in place of "con-
clusion" or "must be true" in place of "infer."

We have to be careful not to mix up Inference and Strengthen questions. Inference questions ask us to
use the argument to support an answer. Strengthen questions ask us to use an answer to support the
argument.

Inference arguments will not contain conclusions or assumptions, so don't waste time trying to find
conclusions or brainstorm assumptions! (And that lack of a conclusion is another way by which we can
distinguish between Inference and Strengthen questions — Inference arguments never have conclusions,
and Strengthen arguments always do.)

The correct answer to an inference question must be true according to the information given in the
argument. The correct answer does not have to use all of the information given in the argument.

Trap answers will include Real World inferences — they're reasonable and could he true, but they don't
have to be true. Inference questions also often include Reverse Direction or Switch Terms traps. These
traps will often contain language that is very similar to the language in the argument, but the trap will
mix up the order of what the argument actually said.

MANHATTAN
GMAT

Evidence Family Chapter 6

Explain a Discrepancy

As was the case with Inference questions, Discrepancy questions consist only of premises, mostly on the
fact-based side (though it is possibly to have more claim-like premises). There are no conclusions. Most
of the time, two sets of premises will be presented, and those premises will be contradictory in some
way. They won't "make sense" together. Sometimes, the argument will include indicator words such as
surprisingly or yet.

Most discrepancy question stems will include some form of the words "explain" or "resolve" and the vast
majority will also contain the words "if true." Here are two typical examples:

Which of the following, if true, most helps to resolve the paradox described
above?

Which of the following, if true, best explains the fact that many economists no
longer recommend curbing spending in order to increase currency values?

Our task on Discrepancy questions is to find an answer that resolves or fixes the discrepancy — that
makes all of the information make sense together. If we leave the argument as is, people should say,
"Wait. That doesn't make sense." If we insert the correct answer into the argument, people should say,
"Oh, I see. That makes sense now."

Take a look at this short example.

According to researchers, low dosages of aspirin taken daily can significantly
reduce the risk of heart attack or stroke. Yet doctors have stopped recommending
daily aspirin for most patients.

Which of the following, if true, most helps to explain why doctors no longer rec-
ommend daily low dosages of aspirin?

(A) Only a small percentage of patients have already experienced a heart attack
or stroke.

(B) Patients who are at low risk for heart attack or stroke are less likely to comply
with a doctor's recommendation to take aspirin daily.

The question stem asks us to "explain" something that doesn't make sense: the aspirin is apparently
beneficial but "doctors have stopped recommending" its use for most people (implying that they did
used to recommend it more). Why would they do that? We might sketch or think of our info visually in
this way:

MANHATTAN
GMAT

Chapter 6

Evidence Family

daily asp I
hrt att / strk

BUT
WHY?

Drs stop for most

Note that, for Discrepancy questions, we didn't set up a core. Not only don't we have a conclusion, but
were not even trying to find a conclusion (as we were on Inference questions). Were trying to find a
third premise that will help these two facts to make sense together. In this case, what we want to do is
highlight the apparent discrepancy between the two facts: on the one hand, daily aspirin is beneficial,
and, on the other, doctors have stopped recommending it.

Back to step 3: what's our goal?

So far, they've told me something really good about taking aspirin daily: it significantly reduces the risk of
some pretty bad things. The fact that the doctors have stopped recommending it means that they used to
recommend it, so why would they stop doing so? Maybe there's something else that's bad about taking aspirin
daily.

(A) Only a small percent-
age of patients have already
experienced a heart attack
or stroke.

ED ABC
daily asp 4 hrt att, strk
BUT drs stop rec for most

(B) Patients who are at
low risk for heart attack
or stroke are less likely to
comply with a doctor's
recommendation to take
aspirin daily.

ED ABC
daily asp 4 hrt att, strk
BUT drs stop rec for most

So maybe this means the doctors think
it wont help that many people? Wait.
The purpose of taking the aspirin is to
try to prevent a heart attack or stroke. If
most people haven t had a heart attack or
stroke, you'd want them to do something
that would help lower the risk.
I can believe this is true in the real world,
but that doesn't affect a doctor's behavior.
They don't say, "Oh, I know a lot of people
won't take the life-saving medication prop-
erly, so I just won't bother to prescribe it."
Plus, why would they recommend aspirin
to people who are at low risk?
Oh, this is a bad thing about aspirin — it
can cause you to bleed internally. The
brain? Yeah, if it could make your brain
start bleeding, I can imagine that doctors
would want to avoid prescribing it unless
there were a really good reason to do so.

The fact that doctors once prescribed daily aspirin but mostly stopped is perplexing when all we're told
is that daily aspirin does something good. Possibly that benefit doesn't apply to most people so the doc-
tors don't waste time recommending the daily treatment. Alternatively, maybe there's some other bad

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thing going on to make the doctors stop prescribing daily aspirin. In this case, answer C gives us that

Answer A tries to get us to think about the first possibility: maybe it doesn't really help very many
people, so the doctors don't bother. However, answer A limits the group to those who have already had
a heart attack or stroke — but the argument is not limited to that group. Answer A does nothing to
explain why the doctors stopped prescribing the treatment to most people.

Answer B again tries to distract us: patients wouldn't benefit if they didn't actually take the medication.
That's true, but this doesn't explain why doctors would stop recommending aspirin. In addition, this
choice limits itself to those who are at low risk for heart attack or stroke — why would doctors need to
recommend daily aspirin for a group that doesn't have the risk factors?

Let's try this again, this time with a full example:

In a recent poll, 71% of respondents reported that they cast votes in the most
recent national election. Voting records show, however, that only 60% of eligible
voters actually voted in that election.

Which of the following pieces of evidence, if true, would provide the best expla-
nation for the discrepancy?

(A) The margin of error for the survey was plus or minus five percentage points.

(B) Fifteen percent of the survey's respondents were living overseas at the time
of the election.

(C) Prior research has shown that people who actually do vote are also more
likely to respond to polls than those who do not vote.

(D) Some people who intend to vote are prevented from doing so by last-min-
ute conflicts on election day or other complications.

(E) People are less likely to respond to a voting poll on the same day that they

bad thing.

voted.

Step 1: Identify the question.

Which of the following pieces of ED A B C D E
evidence, if true, would provide
the best explanation for the
discrepancy ?

The question stem uses the word
"explanation" and explicitly men-
tions a " discrepancy," so this is an
Explain the Discrepancy question.

Chapter 6

Evidence Family

Step 2: Deconstruct the argument.

In a recent poll, 71% of respon-
dents reported that they cast
votes in the most recent national
election.

Voting records show, however,
that only 60% of eligible voters
actually voted in that election.

ED A B C D E
poll: 71% voted in elec

ED A B C D E

poll: 71% voted in elec

records: 60% of elig voters
voted

j Pure fact. There was a poll, and
71% of the people who responded
said they voted in the last election.

Okay, that's strange. Records show
that only 60% of people who were
\ allowed to vote actually voted.

Step 3: State the Goal,

How can it be the case that, when asked, 71% of the people said they voted, but records show only 60%
of those who were allowed to vote actually voted? I don't think it would be because some people voted who
weren't allowed to — I guess that would technically resolve the discrepancy, but I doubt the GMATis going
to say that! So what could it have been? Maybe some people are remembering incorrectly or mixed up the elec-
tion in question. Oh, I know! Polls always have a margin of error, so maybe the margin of error accounts for
the discrepancy.

Okay, I need to find something that will make the whole thing make sense — it'll explain why 71% said they
voted but records showed that only 60% actually voted.

Step 4: Work from wrong to right

(A) The margin of error
for the survey was plus
or minus five percentage
points.

(B) Fifteen percent of
the survey s respondents
were living overseas at
the time of the election.

ED A B C D E

poll: 71% voted in elec

records: 60% of elig voters
voted

ED A B C D E

poll: 71% voted in elec

records: 60% of elig voters
voted

Margin of error, bingo! Excellent. So the real
\ percentage could've been anywhere from. . .
\ 71% + 5% to 71%- 5%.. . which is still
66%. This doesn't go far enough. Still, it's
about margin of error. I'm going to mark this
one and come back to it later.
This percentage is larger than the 11%
discrepancy mentioned in the argument. But
what group are they talking about? Are these
the people who did vote, or didn't vote, or
some mix of the two? And what does "living
overseas" imply? This country might allow
people to vote by absentee ballot. This doesn't
resolve any thing

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Chapter 6

(C) Prior research has
shown that people who
actually do vote are also
more likely to respond
to polls than those who
do not vote.

AfiCDE

(D) Some people who
intend to vote are pre-
vented from doing so
by last-minute conflicts
on election day or other
complications.

(E) People are less likely
to respond to a voting
poll on the same day
that they voted.

poll: 71% voted in elec

records: 60% of elig voters
voted

A ft C B E

poll: 71% voted in elec

records: 60% of elig voters
voted

ED A ft (QBE
poll: 71% voted in elec

records: 60% of elig voters
voted

People who vote are also more likely to re-
spond to a survey. What does that mean? Of
the people who responded, more were likely
to have been voters than is represented in the
overall population. Oh, I see — the survey
group was skewed towards those who voted.
That's why 71% of that sub-group could have
voted while only 60% of the overall popula-
tion of eligible voters voted. That's better than
A — F 11 get rid of A.

Vm sure this is true in the real world. How
does it affect this argument? The survey
took place after the election; it asked people
whether they had voted in the past. It doesnt
address what people intended to do before the
election.

We have no idea when the poll was taken,
sol cant do much with this. Even if the
poll were done the same day as the election,
this just highlights the discrepancy — its
even more puzzling now. I would expect the
percentage of people who said they voted to be
lower than the real percentage because those
who didnt vote that day would be more likely
to agree to participate in the poll.

Common Trap Answers

One common wrong answer trap will seem to be on topic because it will address one of the premises,
but it won't actually resolve the discrepancy between the two premises. This trap answer is actually
Out Of Scope because it doesn't address the discrepancy between the premises. Some of these will be
more obviously out of scope, such as answer D, while others will be trickier because they just don't go
quite far enough, such as answer A. If answer A had said that the margin of error was plus or minus 15
percentage points, that could have been the correct answer.

We can also see Reverse Logic traps, where the answer choice actually highlights or points out the dis-
crepancy — that is, the answer tells us that there is a discrepancy rather than providing new information
to show that there really isn't a discrepancy.

MANHATTAN
GMAT

Chapter 6

Evidence Family

Takeaways for Explain a Discrepancy Questions

Discrepancy question stems will usually contain the words "explain" or "resolve" as well as the words "if
true" (or synonyms).

The argument will consist of premises only; it will not contain a conclusion. The premises will not
make sense together. Upon reading the argument, we should think, "Hmm, why would those two
things both happen? That doesn't make sense!"

The correct answer will resolve the discrepancy — that is, the correct answer will show that there really
isn't any discrepancy at all. If we insert the correct answer into the argument, we should be able to say,
"Oh, okay, that makes sense now."

The most common trap answers will try to address something in the argument but will be Out Of
Scope in some way. Perhaps the answer will address only one premise and not the other. Perhaps the
answer will discuss a group that isn't at issue or a circumstance that occurred at the wrong time. The
trickiest wrong answers of this type will address both premises but won't go far enough to resolve the
discrepancy.

We may also see Reverse Logic trap answers, which will highlight or point out the discrepancy rather
than fix it. These can be tricky if we forget that our task is to fix the discrepancy, not point out what
the discrepancy is.

EXCEPT Questions

As we saw with Assumption Family questions, Evidence Family questions can also be presented in the
negative "Except" format. These are more likely to occur on Discrepancy questions than on Inference
questions.

A regular Discrepancy question might read:

Which of the following, if true, would best help to explain the surprising finding?
An EXCEPT Discrepancy question might read:

Each of the following, if true, could help to explain the surprising finding EXCEPT:

What is the difference in wording between those two questions?

The first one tells us that one answer choice, and only one, explains the discrepancy. That is the answer
choice that we want to pick.

MANHATTAN
GMAT

Evidence Family

Chapter 6

The second one tells us that four answer choices explain the discrepancy. These four are all wrong an-
swers. The fifth answer will NOT explain or resolve the discrepancy. This is the "odd one out" and, as
we saw in the Strengthen and Weaken chapter, its the answer that we want to pick.

Similarly, on an Inference EXCEPT question, four answer choices would represent things that must be
true according to the argument, and we will eliminate these four. One answer will represent something
that does not have to be true; this is our "odd one out" and the correct answer.

MANHATTAN
GMAT

Evidence Family

Problem Set

Chapter 6

1 . Nitrogen Triiodide

Nitrogen triiodide is a highly explosive chemical that is easy to make from only
two ingredients: ammonia and concentrated iodine. However, nitrogen triiodide
has never been known to be used in a terrorist or criminal attack.

Which of the following, if true, is the most likely explanation for the discrepancy
described above?

(A) Ammonia can be bought in a grocery store, but concentrated iodine must
be obtained from somewhat more restricted sources, such as chemical sup-
ply houses.

(B) Nitrogen triiodide is only one of several powerful explosives that can be
made from ammonia.

(D) Airport security devices are typically calibrated to detect nitrogen com-
pounds, such as ammonia and ammonium compounds.

(E) Nitrogen triiodide is extremely shock sensitive and can detonate as a result
of even slight movement.

2. Mycenaean Vase

Museum A will display only undamaged objects of proven authenticity. Doubts
have been raised about the origins of a supposedly Mycenaean vase currently on
display in the museum's antiquities wing. The only way to establish this vase's au-
thenticity would be to pulverize it, then subject the dust to spectroscopic analysis.

The claims above, if true, most strongly support which of the following conclu-
sions?

(A) Authentic Mycenaean vases are valuable and rare.

(B) Museum A has been beset with questions about the provenance of many of
the items in its antiquities wing.

(D) Spectroscopic analysis has revolutionized the forensic investigation of art
forgery.

(E) Knowingly or not, many of the world's museums display some forgeries.

MAN

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Evidence Family

3. Gas Mileage

The average fuel efficiency of vehicles sold nationwide during the period 2000-
2004 was 25 miles per gallon; the corresponding figure during the period 1995-
1999 was 20 miles per gallon. The national average price of gasoline during the
period 2000-2004 was $2 per gallon; the corresponding figure during the period
1995-1999 was $1.60 per gallon.

The statements above, if true, best support which of the following conclusions?

(A) The average fuel efficiency of vehicles sold nationwide should reach 30
miles per gallon for the period 2005-2009.

(B) The national average price of gasoline during 1997 was lower than the cor-
responding price during 2003.

(D) Between the two described time periods, the national average fuel effi-
ciency and the national average gasoline price both increased at roughly the
same rate.

(E) Consumers spent more money on gasoline during the period 2000-2004
than during the period 1995-1999.

4. CarStore

CarStore's sales personnel have an average of fifteen years' experience selling
automobiles, and they regularly sell more cars than other local dealers. Despite
this, CarStore has recently implemented a mandatory training program for all
sales personnel.

Which of the following, if true, best explains the facts given above?

(A) The sales personnel in CarStore have historically specialized in aggressively
selling automobiles and add-on features.

(B) Salespeople at other local dealers average 10 years' experience.

(D) Pricing information, which used to be confidential, has recently been re-
leased on the internet, and many customers try to negotiate lower prices
using this data.

(E) Several retailers that compete directly with CarStore use "customer-cen-
tered" sales approaches.

MANHATTAN
GMAT

Evidence Family

5. Stem Cell Research

Government restrictions have severely limited the amount of stem cell research
United States companies can conduct. Because of these restrictions, many United
States scientists who specialize in the field of stem cell research have signed long-
term contracts to work for foreign companies. Recently, Congress has proposed
lifting all restrictions on stem cell research.

Which of the following statements can most properly be inferred from the infor-
mation above?

(A) Some foreign companies that conduct stem cell research work under fewer
restrictions than some United States companies do.

(B) Because United States scientists are under long-term contracts to foreign
companies, there will be a significant influx of foreign professionals into the
United States.

(D) In the near future, United States companies will no longer be at the forefront
of stem cell research.

(E) If restrictions on stem cell research are lifted, many of the United States sci-
entists will break their contracts to return to United States companies.

6. Hunting Season

In an effort to reduce the number of deer, and therefore decrease the number of
automobile accidents caused by deer, the government lengthened the deer hunt-
ing season earlier this year. Surprisingly, the number of accidents caused by deer
has increased substantially since the introduction of the longer hunting season.

All of the following, if true, help to explain the increase in traffic accidents caused
by deer EXCEPT:

(A) The presence of humans in the woods causes the deer to move to new areas,
which causes the deer to cross roads more frequently than normal.

(B) In the area where the deer live, traffic has increased substantially precisely
because of the lengthened hunting season.

(C) Most automobile accidents involving deer result from cars swerving to avoid
deer, and leave the deer in question unharmed.

(D) Deer tend to bolt when hearing gunshots or other loud sounds and are
more likely to run across a road without warning.

(E) A new highway was recently built directly through the state's largest forest,
which is the primary habitat of the state's deer population.

Chapter 6

Evidence Family

7. World Bank

In 2010, China comprised about 10 percent of the world's gross domestic product
(GDP), and its voting share in the World Bank was increased from under 3 percent
to 4.4 percent. During the same timeframe, France comprised about 4 percent of
the world's GDP and saw its voting share in the World bank drop from 4.3 percent
to 3.8 percent.

Which of the following can be logically concluded from the passage above?

(A) World Bank voting shares are allocated based upon each country's share of
the world's GDP.

(B) The new ratio of voting share to percentage of world GDP is lower for China
than it is for France.

(D) China should be upset that its voting share does not match its proportion of
the world's GDP.

(E) France lost some of its voting share to China because China comprised a

Two-dimensional bar codes are omni-directional; that is, unlike one-dimensional
bar codes, they can be scanned from any direction. Additionally, two-dimensional
bar codes are smaller and can store more data than their one-dimensional coun-
terparts. Despite such advantages, two-dimensional bar codes account for a
much smaller portion of total bar code usage than one-dimensional bar codes.

Which of the following, if true, most helps to resolve the apparent paradox?

(A) Many smaller stores do not use bar codes at all because of the expense.

(B) For some products, the amount of data necessary to be coded is small
enough to fit fully on a one-dimensional bar code.

(D) Two-dimensional bar codes can also be scanned by consumer devices, such
as cell phones.

(E) One-dimensional bar codes last longer and are less prone to error than two-
dimensional bar codes.

8. Bar Codes

larger portion of the world's GDP.

210

MANS*
GMAT

HATTAN

Evidence Family

Chapter 6

Solutions

1. Nitrogen Triiodide: The correct answer is E.
Step 1: Identify the question.

Which of the following, if true,
is the most likely explanation
for the discrepancy described
above?

Step 2: Deconstruct the argument.

Nitrogen triiodide is a highly
explosive chemical that is easy
to make from only two ingredi-
ents: ammonia and concentrated
iodine.

However, nitrogen triiodide has
never been known to be used in
a terrorist or criminal attack.

Step 3: State the Goal.

A B C D E

The word "discrepancy" indicates
that this is a Discrepancy ques-
tion.

ED A B C D E
NT expl, easy to make

ED A B C D E

NT expl, easy to make

BUT never used by terr or
crims

This is a fact. I think the main
point is that it's easy to make,
not that I need those two specific
chemicals y so Tm not going to
write them down.
That's weird. If it's so easy to
make, why haven t criminals and
terrorists used it? Maybe it's hard
to get one of the ingredients, or
they're really expensive?

This is a Discrepancy question, so the argument will provide two seemingly contradictory pieces of informa-
tion. I need to find something that will make everything make sense.

In this case, there's an explosive that's easy to make, and yet criminals have never used it. I need to find some-
thing that explains why.

Step 4: Work from wrong to right.

(A) Ammonia can be
bought in a grocery
store, but concentrated
iodine must be obtained
from somewhat more re-
stricted sources, such as
chemical supply houses.

ED A B C D E
NT expl, easy to make

This is kind of like what I said before — it's
harder to get one of the chemicals. This might
explain it. . . except it doesn't say that you
BUT never used by terr or can't get iodine. It just says you have to go to
cr i ms a special place, but you can still get it. So I'm

not sure that really explains why no criminals
have ever used it. I'll leave this in until I find
something better.

MANHATTAN
GMAT

er 6

Evidence Family

(B) Nitrogen triiodide is
only one of several pow-
erful explosives that can
be made from ammonia.

(D) Airport security
devices are typically
calibrated to detect ni-
trogen compounds, such
as ammonia and ammo-
nium compounds.

(E) Nitrogen triiodide is
extremely shock sensi-
tive and can detonate

as a result of even slight
movement.

ED ABCDE

NT expl, easy to make

BUT never used by terr or
crims

ED ABGDE

NT expl, easy to make

BUT never used by terr or
crims

ED A fi € © E

NT expl, easy to make

BUT never used by terr or
crims

So you can make even more explosives from
this chemical? That doesn't explain why the
criminals have never made it.

Again, this doesnt explain why they haven t
used the NT explosive. Maybe if TNT
or PETN are a lot cheaper or easier to
make — but this choice doesnt say that.

This might explain why no one has tried
to bring these explosives into airports, but
it doesnt explain why these explosives have
never been used in any type of attack any-
where.

Here we go. If the bomb is so unstable that it
could go off at any moment, including right
after you make it, then it makes sense that
BUT never used by terr or criminals dont want to use these explosives.
cnms This is better than answer A.

2. Mycenaean Vase: The correct answer is C.
Step 1: Identify the question.

The claims above, if true, most In ABCDE
strongly support which of the
following conclusions?

Step 2: Deconstruct the argument.

Museum A will display only
undamaged objects of proven
authenticity.

ABCDE

MA: only perfect, auth
objects

The language "strongly support"
could indicate an Inference or a
Strengthen question. The question
stem indicates that the answer
choice contains the conclusions,
though (and the argument didnt
have a conclusion), so this is an
Inference question.

This is a fact — all objects have to
be perfect and authenticated for
MA to display them.

MANHATTAN
GMAT

Evidence Family

Doubts have been raised about
the origins of a supposedly
Mycenaean vase currently on
display in the museums antiqui-
ties wing.

The only way to establish this
vases authenticity would be to
pulverize it, then subject the
dust to spectroscopic analysis.

Step 3: Stat e the Goal.

In A B C D E

MA: only perfect, auth
objects

MV: auth doubtful
In A B C D E

MA: only perfect, auth
objects

MV: auth doubtful

to auth M V, must destroy it

Another fact: they're not sure
whether this vase is authentic.

That's interesting. In order to
prove whether the vase is authen-
tic, you ve got to destroy it!

This is an Inference question; I need to find something that must be true according to the info given in the ar-
gument. In this case, they re not sure whether this vase is authentic, and the only way to establish its authen-
ticity is to destroy it. But then they cant display it anymore because they'll only display it if it's perfect!

Step 4: Work from wron g to rig ht.

(A) Authentic Myce-
naean vases are valuable
and rare.

In A B C D E

MA: only perfect, auth
objects

MV: auth doubtful

to auth MV, must destroy

This might be true, but it doesn't have to be
true. The argument says nothing about value
or rarity.

(B) Museum A has been
beset with questions
about the provenance of
many of the items in its
antiquities wing.

In A © C D E

MA: only perfect, auth
objects

MV: auth doubtful

to auth MV, must destroy
it

In ABCDE

MA: only perfect, auth
objects

MV: auth doubtful

to auth MV, must destroy
it

The argument is only about one particular
vase. Any other items are out of scope.

This is exactly what I said before! If they try
to authenticate it, they'll destroy the vase, in
which case they can't display it. And if they
dont try to authenticate it, then they won't
know whether it's authentic, in which case
Museum A still won't display it. This has
to be true (though I'll check the other two
answers to be sure).

Chapter 6

Evidence Family

(D) Spectroscopic analy-
sis has revolutionized
the forensic investiga-
tion of art forgery.

ABCBE

(E) Knowingly or not,
many of the world's
museums display some
forgeries.

MA: only perfect, auth
objects

MV: auth doubtful

to auth MV, must destroy
it

In Afi©©£

MA: only perfect, auth
objects

MV: auth doubtful

to auth M V, must destroy
it

This might be true, but it doesn't have to be
true that it "revolutionized" the field. It just
has to work in general.

I can believe that this is probably true, but it
doesn't absolutely have to be true.

.... ..

3. Gas Mileage: The correct answer is D.
Step 1: Identify the question.

The statements above, if true,
best support which of the fol-
lowing conclusions ?

Step 2: Deconstruct the argument.

The average fuel efficiency of
vehicles sold nationwide dur-
ing the period 2000-2004 was
25 miles per gallon; the cor-
responding figure during the
period 1995-1999 was 20 miles
per gallon.

A B C D E

95-99

00-04

AFE 20

AFE 25

The language "best support"
could indicate an Inference or a
Strengthen question. The question
stem indicates that the answer
choice contains the conclusions,
though (and the argument didn't
have a conclusion), so this is an
Inference question.

These are all facts, which I'm
expecting because this is an Infer-
ence question. They're talking
about time periods and figures, so
maybe a table is the best way to
keep track.

214

GMAT

Evidence Family

A B C D E

95-99

00-04

AFE 20

AFE 25

AG $1.60

AG $2

Yep, a table was a good ideal
More facts and figures for the
same timeframe.

The national average price
of gasoline during the period
2000-2004 was $2 per gallon;
the corresponding figure during
the period 1995-1999 was $1.60
per gallon.

Step 3: State the Goal.

This is an Inference question, so I'm looking for something that must be true based on all this data. I was
given specific figures for average fuel efficiency and average gas price for two time periods. Both went up over
time.

Step 4: Work from wrong to rig ht.

(A) The average fuel ef-
ficiency of vehicles sold
nationwide should reach
30 miles per gallon for
the period 2005-2009.

(B) The national average
price of gasoline during
1997 was lower than
the corresponding price
during 2003.

(D) Between the two
described time periods,
the national average fuel
efficiency and the na-
tional average gasoline
price both increased at
roughly the same rate.

A B C D E

95-99

00-04

AFE 20

AFE 25

AG $1.60

AG $2

In AfiCDE

95-99

00-04

AFE 20

AFE 25

AG $1.60

AG $2 !

In ABODE

95-99

00-04

AFE 20

AFE 25 !

AG $1.60

AG $2

In A B € D E

95-99

00-04

AFE 20

AFE 25

AG $1.60

AG $2

"Should reach?" That doesnt have to be true.
Who knows what s going to happen in the
future?

The data given is only for the 5-year periods
95 to 99 and 00 to 04. 1 have no idea what
the numbers were for 1997 and 2003 specifi-
cally.

That might be true, but it doesnt have to
be true. The argument doesnt say anything
about why consumers decide to purchase
certain cars.

Increased at the same rate? Hmm. I dont
know, but I can calculate based on the figures
I was already given. The AFE figure went
from 20 to 25. The increase, then, was 5 over
a base (or starting point) of 20. 5/20 = 1/4,
or a rate of 25%. The AG figure went from
1.6 to 2, which is an increase of 0.4 over a
starting point of 1.6. 0.4/1.6= 1/4, or a rate
of 25% again. Hey, this is true!

Chapter 6

Evidence Family

(E) Consumers spent
more money on gaso-
line during the period
2000-2004 than during
the period 1995-1999.

In AB6@E

95-99

00-04

AFE 20

AFE 25

AG $1.60

AG $2

Tricky! This one seems pretty good at first
glance, but average price per gallon is not the
same thing as total amount of money spent.
Its true that the average price was higher, but
maybe people bought fewer gallons of gasoline
(especially because fuel efficiency was better!).
This one might be true, but it doesnt have to
be.

4. CarStore: The correct answer is D.

Step 1: Identify the question.

Which of the following, if true,
best explains the facts given
above?

Step 2: Deconstruct the argument.

CarStore s sales personnel have
an average of fifteen years'
experience selling automobiles,
and they regularly sell more cars
than other local dealers.
Despite this, CarStore has
recently implemented a manda-
tory training program for all
sales personnel.

Step 3: State the Goal.

A B C D E

SP: avg 15y exp; sell more
than comp

ED A B C D E

SP: avg 15y exp; sell more
than comp

BUT CSreq trngfor all

The language "best explains the
facts" is a slightly unusual form for
a Discrepancy question.

CarStore s people have 15 years'
experience on average, and they
sell more cars than the competi-
tion. These are facts.

i Here's the contrast. Why are they
going to make them all go through
training! Maybe something has
changed in the marketplace?

This is a Discrepancy question, so I need to find an answer that explains why these two facts are actually
NOT contradictory after all. What would explain why CS is requiring its employees to go through new train-
ing? Maybe something has changed in the marketplace that would require new training.

216

GMAT

Evidence Family

Step 4: Work from wrong to rig ht.

(A) The sales person-
nel in CarStore have
historically specialized
in aggressively selling
automobiles and add-on
features.

(B) Salespeople at other
local dealers average 10
years' experience.

(D) Pricing informa-
tion, which used to be
confidential, has re-
cently been released on
the internet, and many
customers try to negoti-
ate lower prices using
this data.

(E) Several retailers that
compete directly with
CarStore use "customer-
centered" sales ap-
proaches.

ED A B C D E

SP: avg 15y exp; sell more
than comp

BUT CS req trng for all

ED ABCDE

SP: avg 15y exp; sell more
than comp

BUT CS req trng for all
ED ABCDE

SP: avg 15y exp; sell more
than comp

BUT CS req trng for all
ED ABCDE

SP: avg 15y exp; sell more
than comp

BUT CS req trng for all

ED Afi€®E

SP: avg 15y exp; sell more
than comp

BUT CS req trng for all

IfCS wants to change the way their people
sell cars, then new training would make
sense. . . but this choice just talks about what
they've done in the past, not what they want
to do in the future. This doesnt explain the
discrepancy.

So the CS people are more experienced, on
average, than other salespeople in the area.
If anything, this just accentuates the discrep-
ancy: why do the more experienced people
need training!

This makes sense, but again does not explain
why the employees who average 15 years'
experience need training. The argument said
that all sales personnel have to undergo the
training, not just the new ones.
Ah, so the situation has changed. Customers
now know some info that used to be confi-
dential. That might change negotiations, so
it makes sense that the salespeople might need
new training.

Thats what they already use — the answer
doesnt indicate that anything has changed.
Nor does it indicate that CS doesnt use a
customer-centered approach or that consum-
ers prefer a customer-centered approach.
This doesnt explain why the CS people need
training.

Chapter 6

Evidence Family

5. Stem Cell Research: The correct answer is A.
Step 1: Identify the question.

Which of the following state-
ments can most properly be
inferred from the information
above?

Step 2: Deconstruct the argument.

Government restrictions have
severely limited the amount of
stem cell research United States
companies can conduct.
Because of these restrictions,
many United States scientists
who specialize in the field of
stem cell research have signed
long-term contracts to work for
foreign companies.
Recently, Congress has proposed
lifting all restrictions on stem
cell research.

A B C D E

In A B C D E
SCR restrict by US govt

In A B C D E

SCR restrict by US govt ~<
US sci work foreign corns
instead

A B C D E

SCR restrict by US govt -»
US sci work foreign corns
instead

US gov: maybe lift restrict?

The word " inferred" indicates
that this is an Inference question.

j This is a fact. The US government
j restricts this stem cell research
(SCR).

"Because of" that — so the first
sentence leads to the second sen-
tence.

Still a fact: the government is
j considering lifting the restrictions.
Maybe that* 11 bring the scientists
back to work for US companies?

Step 3: Sta te the Goal.

This is an Inference question, so I need to find something that must be true based on the info given so far.
The US government restricts a certain kind of research, so many US scientists who do this type of research are
working for foreign companies instead. Congress might lift the restrictions.

218

GMAT

Evidence Family

Step 4: Work from wrong to right.

(A) Some foreign
companies that conduct
stem cell research work
under fewer restrictions
than some United States
companies do.

(B) Because United
States scientists are un-
der long-term contracts
to foreign companies,
there will be a signifi-
cant influx of foreign
professionals into the
United States.

(D) In the near future,
United States companies
will no longer be at the
forefront of stem cell
research.

(E) If restrictions on
stem cell research are
lifted, many of the Unit-
ed States scientists will
break their contracts to
return to United States
companies.

In ABCDE

SCR restrict by US govt -*
US sci work foreign corns
instead

US gov: maybe lift restrict?

In ABCDE

SCR restrict by US govt ->
US sci work foreign corns
instead

US gov: maybe lift restrict?

In ABCDE

SCR restrict by US govt
US sci work foreign corns
instead

US gov: maybe lift restrict?
In ABCDE

SCR restrict by US govt
US sci work foreign corns
instead

US gov: maybe lift restrict?
In ®B € D E

SCR restrict by US govt -»
US sci work foreign corns
instead

US gov: maybe lift restrict?

If the researchers decided to work for for-
eign companies specifically because the U.S.
companies had restrictions, then that would
mean that at least some foreign companies did
have fewer restrictions. Yes, this one must be
true! I'll check the other answers just in case,
though.

This might be true, but it certainly doesn't
have to be true. The argument doesn't say
anything about foreign professionals coming
into the U.S.

The argument doesn't say anything about how
this type of research gets its financial backing
This doesn't have to be true.

Out of scope. The argument doesn't discuss
who is or will be at the forefront of this kind
of research.

Maybe this will happen, but it doesn't have to
happen. It isn't easy to break a contract.

Chapter 6

Evidence Family

6. Hunting Season: The correct answer is C.
Step 1: Identify the question.

Q stem All of the following, if
true, help to explain the increase
in traffic accidents caused by
deer EXCEPT.

ED Ex A B C D E

The language "help to explain"
indicates that this is a Discrepan-
cy question. This is also an Except
question.

Step 2: Deconstruct the argument.

In an effort to reduce the
number of deer, and therefore
decrease the number of automo-
bile accidents caused by deer,
the government lengthened the
deer hunting season earlier this
year.

Surprisingly, the number of
accidents caused by deer has
increased substantially since the
introduction of the longer hunt-
ing season.

Step 3: State the Goal.

ED Ex A B C D E

G: t HS -> I #D -> I #car
acc from D

ED Ex A B C D E

G: T HS -> I #D -* I #car
acc from D

BUT # car acc t

Multiple levels here. First, the
| government lengthened hunt-
\ ing season, which is supposed to

reduce the number of deer, which
\ is then supposed to reduce the

number of car accidents caused by

deer.

That's weird. The exact opposite
has happened: there have been
more car accidents caused by deer!

This is a Discrepancy Except question. Normally on discrepancy questions, I'm looking for the answer that
makes the contradictory evidence make sense. On this one, though, all four wrong answers will fix the discrep
ancy. The "odd one out" — the one that doesnt fix the discrepancy — will be the right answer.

So I need to find (and cross off) four things that explain why there have been even more car accidents caused
by deer.

Step 4: Work from wrong to rig ht.

(A) The presence of
humans in the woods
causes the deer to move
to new areas, which
causes the deer to cross
roads more frequently
than normal.

ED Ex A B C D E

G: t HS -> i #D -» I
#car acc from D

BUT # car acc f

If hunting season is lengthened, then there
will be people in the woods for a longer period
of time. According to this choice, that means
the deer are going to cross the roads more
frequently than they otherwise would have.
That could increase the likelihood of accidents
due to deer, which explains the discrepancy.
Cross this one off.

220

GMAT

Evidence Family

Chapter 6

(B) In the area where
the deer live, traffic has
increased substantially
precisely because of the
lengthened hunting

ED Ex

AfiCDE

season.

(C) Most automobile
accidents involving deer
result from cars swerv-
ing to avoid deer, and
leave the deer in ques-
tion unharmed.

(D) Deer tend to bolt
when hearing gunshots
or other loud sounds
and are more likely to
run across a road with-
out warning.

(E) A new highway was
recently built directly
through the states larg-
est forest, which is the
primary habitat of the
state s deer population.

G: t HS -> A #D -» A
#car acc from D

BUT # car acc t

ED Ex A fi C D E

G: t HS -> A #D -> A
#car acc from D

BUT # car acc t

G: t HS -> A #D -> A
#car acc from D

BUT # car acc t

ED Ex

A BO© E

G: t HS -> A #D -> A
#car acc from D

BUT # car acc t

Oh, this makes sense. The lengthened hunting
season actually caused more traffic, so there
are more chances for accidents between cars
and deer where the deer live. This explains
the discrepancy, too.

This one is tricky! It sounded like it explained
the discrepancy when I first read it, but then
I realized something: its just explaining how
the accidents tend to happen, but it doesnt
address why there are MORE accidents now
than there used to be.

Ah, so if there are gunshots for a longer length
of time, then there are more chances for the
deer to bolt and cross the road suddenly. . .
increasing the chances of an accident.

The situation has changed from the year be-
fore: a new highway was built right through
the area where the deer live. So it would
make sense that there are now more accidents
caused by deer.

7. World Bank: The correct answer is B.

Step 1: Identify the question.

Which of the following can be
logically concluded from the
passage above?

Step 2: Deconstruct the argument.

In 2010, China comprised about
10 percent of the world s gross
domestic product (GDP), and
its voting share in the World
Bank was increased from under
3 percent to 4.4 percent.

In A B C D E

2010

GDP

<3 -» 4.4

The language "logically con-
cluded" indicates that this is an
Inference question.

A bunch of stats about China
in 2010. I just need to keep this
straight because, glancing down, I
can see the next sentence has more
numbers.

MANHATTAN
GMAT

Evidence Family

A B C D E

2010

GDP

<3 -» 4.4

4.3 -* 3.8

S# *y/>£ of stats, but about
France this time. Same time-
frame.

During the same timeframe,
France comprised about 4
percent of the world's GDP and
saw its voting share in the World
bank drop from 4.3 percent to
3.8 percent.

Step 3: State the Goal.

This is an Inference question, so I need to find something that must be true based upon the info given so far.
There are a lot of numbers to keep straight, but generally, China has a larger share of the world GDP than
France. China used to have a lower voting share than France, but now it has a higher share.

Step 4: Work from wrong to rig ht.

(A) World Bank vot-
ing shares are allocated
based upon each coun-
try's share of the world's
GDP.

(B) The new ratio of
voting share to percent-
age of world GDP is
lower for China than it
is for France.

(D) China should be
upset that its voting
share does not match
its proportion of the
world's GDP.

(E) France lost some of
its voting share to China
because China com-
prised a larger portion
of the world's GDP.

A B C D E

2010

GDP

<3 -> 4.4

4.3 -» 3.8

ABCDE

2010

GDP

<3 -> 4.4

4.3 -» 3.8

A B € D E

2010

GDP

<3 -» 4.4

4.3 -> 3.8

A B € & E

2010

GDP

<3 -» 4.4

4.3 -> 3.8

A(g)€ & E

2010

GDP

VS !

<3 -» 4.4

4 |

4.3 -* 3.8

Maybe. It is the case now that China has a
larger GDP and a larger voting share. But it
didn't used to be that way. And we only have
two data points; I don't know the numbers
with all of the other countries. This doesn't
have to be true.

Let's see. China's ratio is 4.4 1 10. And the
ratio for France is 3.8 1 4. The first number
is a lot smaller than the second number: the
first one is 0.44 and the second one is almost
1. So, yes, it's true that China's ratio is lower
than France's.

"Most important?" The argument didn't say
anything about how voting share is deter-
mined or which factor is most important.

China might be upset but this doesn't have to
be true — and it doesn't have to be true that
China "should" be upset. That's a judgment
call

Maybe this is true, but they didn't actually
say why the voting shares were changed. I
could speculate, but this doesn't have to be
true.

Evidence Family

Chapter 6

8. Bar Codes: The correct answer is E.

Step 1: Identify the question.

Which of the following, if true,
most helps to resolve the appar-
ent paradox ?

Step 2: Deconstruct the argument.

Two-dimensional bar codes are
omni-directional; that is, unlike
one-dimensional bar codes, they
can be scanned from any direc-
tion.

Additionally, two-dimensional
bar codes are smaller and can
store more data than their one-
dimensional counterparts.

Despite such advantages, two-
dimensional bar codes account
for a much smaller portion of
total bar code usage than one-
dimensional bar codes.

A B C D E

2D BC scan any dir; ID BC
cant

A B C D E

2D BC scan any dir; ID BC
can't

2D BC smaller, more data
ED A B C D E

2D BC scan any dir; ID BC
can't

2D BC smaller, more data
BUT ID is used »

The word "paradox" indicates
that this is a Discrepancy ques-
tion.

Okay, so 2D barcodes have a bet-
ter feature than ID barcodes.

Even more advantages for the 2D
barcodes.

But the ID barcodes are used a lot
more — why? There must be some
advantages to the IDs or disad-
vantages for the 2Ds.

Step 3: State the Goal.

/ need to find something that fixes the discrepancy described in the argument: the 2D barcodes have a bunch
of advantages, but people mostly still use the ID barcodes. Why? Maybe the 2D ones are super-expensive or
something like that.

Step 4: Work from wrong to rig ht.

(A) Many smaller stores
do not use bar codes
at all because of the
expense.

ED A B C D E Expense — does this explain why ID barcodes

are still being used? No, wait — this says the
stores arent using any type of barcode at all.
So that doesnt explain why the ones who do
2D BC smaller, more data use barcodes seem to prefer the ID models.

BUT ID is used »

2D BC scan any dir; ID
BC cant

GMAT

223

Chapter 6

Evidence Family

(B) For some products,
the amount of data
necessary to be coded is
small enough to fit fully
on a one-dimensional
bar code.

(D) Two-dimensional
bar codes can also be
scanned by consumer
devices, such as cell
phones.

(E) One-dimensional
bar codes last longer and
are less prone to error
than two-dimensional
bar codes.

A © C D E

2D BC scan any dir; ID
BC cant

2D BC smaller, more data

BUT ID is used »
ED A B € D E

2D BC scan any dir; ID
BC cant

2D BC smaller, more data

BUT ID is used »
ED A B € B E

2D BC scan any dir; ID
BC cant

2D BC smaller, more data

BUT ID is used »
ED A B € B(|)

2D BC scan any dir; ID
BC can't

2D BC smaller, more data
BUT ID is used »

Okay, so some products might not need the
2D barcodes. Except, this only mentions
"some" products, while the argument says that
the 2D barcodes are a "much smaller" portion
of total usage. This doesn't fully explain the
discrepancy.

Less expensive, this is it! Wait a second. No,
this says the 2D barcodes are less expen-
sive — that gives them yet another advantage!
If they're less expensive, you'd expect people to
use them more. This isn't it.

This sounds like yet another advantage for the
2D barcodes. This isn't it either!

Ah, here we go. Here are two advantages for
the ID barcodes. If it's true that they last
longer and are less prone to error, then that
would explain why people would want to use
them rather than the 2D barcodes.

224

GMAT

Chapter/7

Critical Reasoning

Complete the Argument

On This Chapter. , .

Negatively-Worded Claims
Alternate Wording

Complete the Argument

Complete the Argument (CA) questions don't fall into any one Family of questions. Rather, "Complete
the Argument" is a structure for writing the argument itself, and any of the question types we've already
discussed could theoretically be written using this structure. In practice, however, most CA questions
resemble Assumption or Strengthen questions; most will ask us to find an answer that makes a claim or
conclusion true or much more likely to be true.

Lets look at an example:

Which of the following most logically completes the argument below?

XYZ Industries sells both a premium line of televisions and a basic line. The
higher-end line sells at a 20% premium but also costs 30% more to produce and
market. The company has announced that it will stop producing premium televi-
sions and sell only the regular line in future. This plan will help to improve profit-
ability since .

Right away, you'll notice that we have no question stem after the argument. Most of the time, the ques-
tion will come before, as in the example above, and the question stem also wont help to tell us anything
other than that we have a "Complete the Argument" structure.

In the vast majority of Complete the Argument (CA) problems, the last sentence will contain a conclu-
sion or claim followed by the word "since" or "because" and a blank. In these cases, the arguments are
asking us to find some kind of a premise that will support the claim given in the same sentence.

In our above example, the author claims that "this plan will help to improve profits." Our task is to find
an answer that will make this claim true or much more likely to be true.

For the above example, for instance, a correct answer might read:

basic televisions are more profitable for the company than are premium televisions

227

Chapter 7

Complete the Argument

If its the case that the basic televisions are more profitable, then getting rid of the less profitable product
and selling only the more profitable product will likely improve overall profitability — this strengthens
the author's case. The interesting thing is that the argument itself gave us enough information to de-
termine that the basic televisions are more profitable. If the company charges 20% more on a premium
television but has to pay 30% more to produce it, then we can conclude that the premium televisions
are less profitable than the basic televisions. The answer choice, then, is almost repeating a premise that
we were already told in the argument.

Contrast that answer with this alternative for a correct answer:

cutting the production of premium televisions will allow XYZ Industries to in-
crease production of its basic television line

In this case, the correct answer provides us with some new information, similar to a strengthen ques-
tion. If its the case that the company can produce even more of the more-profitable basic TVs, then
that again makes it much more likely that this plan will improve overall profitability.

On CA questions, the correct answer might be a restatement of a premise we were already told. Alter-
natively, the correct answer may introduce a new premise. Either way, the result will be the same: the
answer will strongly bolster the author s conclusion.

Negatively-Worded Claims

Many Complete the Argument questions introduce a negatively-worded twist. Take a look at this varia-
tion on our original argument:

Which of the following most logically completes the argument below?

XYZ Industries sells both a premium line of televisions and a basic line. The
higher-end line sells at a 20% premium but also costs 30% more to produce and
market. Producing more televisions from the basic line, however, will not neces-
sarily help to improve profitability since .

These questions will not put the negative wording in capital letters, as we've seen on the "EXCEPT"
question variations. Rather, the conclusion itself is that last sentence: this will not necessarily help to
improve profitability. Why? Consider this possible correct answer:

the market for basic televisions is shrinking

In other words, producing more TVs doesn't necessarily mean we can sell more TVs, and we have to sell
them in order to make money. If the market for basic TVs is shrinking, then producing more of those
TVs wont necessarily be beneficial for the company's profitability.

MANHATTAN
GMAT

Complete the Argument Chapter 7

Alternate Wording

The first two variations we discussed represent the most common ways in which Complete the Argu-
ment questions can be presented. There are a few alternate examples, however, that might pop up.
Students aiming for 90th percentile or higher on the verbal section may want to be prepared for these
rare variations.

The rare variants will still typically include the conclusion or claim in the final sentence with the blank,
but the "lead in" wording to the blank might be different, and what we need to do to find the answer
might be different as well.

"lead in" wording

answer choice should

most resembles?

(something) is "illustrated by"

provide a concrete example of a
premise from the argument

n/a

if (some claim is true), "it
should be expected that"

represent something that must
be true given the information in
the argument

Inference questions

(in order for some claim to be
true) "it must be shown that"

represent something that must
be true given the information in
the argument

Inference questions

Let's look at a full example of one of the more common forms of the Complete the Argument (CA)
question type.

Which of the following best completes the passage below?

The Farmsley Film and Performing Arts Center was built three years ago in down-
town Metropolis. A recent study shows that, on average, a person who attends
a show at the Farmsley Center spends $96 at other downtown businesses on
the day of the show. This fact, however, does not necessarily indicate that the
Farmsley Center is a significant driver of the economic revitalization of downtown
Metropolis, since .

(A) people who do not attend a Farmsley Center show spend $63 on average
when shopping in the downtown area

(B) restaurants near the Farmsley Center tend to be more expensive than restau-
rants in outlying areas

(D) the Farmsley Center is the only downtown theatre large enough to afford to
show newly-released major Hollywood films

(E) most of the people who attend films or performances at the Farmsley Center
do so because they are already in the area to shop

MANHATTAN
GMAT

Chapter 7

Complete the Argument

Step 1 : Identify the question.

Which of the following best
completes the passage below?

CA:S

A B C D E

Step 2: Deconstruct the argument

The Farmsley Film and Per-
forming Arts Center was built
three years ago in downtown
Metropolis.

A recent study shows that, on
average, a person who attends
a show at the Farmsley Center
spends $96 at other downtown
businesses on the day of the
show.

This fact, however, does not
necessarily indicate that the
Farmsley Center is a significant
driver of the economic revital-
ization of downtown Metropo-
lis, since .

CA:S A B C D E
3ya: F built

RS: F ppl spend $96 avg
other stuff

CA:S A B C D E
3ya: F built

RS: F ppl spend $96 avg
other stuff

Step 3; State the Goal,

The blank and the fact that the
\ question appears first both indi-
cate that this is a "Complete the
Argument" question. The word
"since" right before the blank
indicates that this is likely a clas-
sic "Strengthen the Conclusion"
variation.

Pure fact. Fm not even sure I
need to write this down.

It sounds like the other businesses
in the downtown area should be
happy that the F place is there.

Oh, wait — but this is saying that
the $96 thing is NOT necessar-
ily evidence that F is one of the
businesses driving the "economic

\ revitalization" of the area. That's

\ interesting

The conclusion said that F is not necessarily driving Ms economic revitalization (so it could be contributing,
but it also might not be). "Revitalization" implies that the economy was worse for a while but has been getting
better lately, and F was just built 3 years ago, so that would be a (very small) point in favor ofF helping drive
the revitalization.

Plus, the other piece of evidence sounds pretty good: that people spend nearly a hundred bucks in other stores
on the day of a performance. So why is that F isn't necessarily driving Ms revitalization? Maybe people ordi-
narily spend $150 if they don't attend a show, so they spend less if they see a show at F? I was just assuming
that the $96 figure was a good figure; maybe it's not.

MANHATTAN
GMAT

Complete the Argument

Chapter?

/ need to find a piece of evidence that makes the claim at least a little more likely to be true — that F isnt
necessarily a major driver in revitalizing Ms economy.

Step 4: Work from wrong to right

(A) people who do not
attend a Farmsley Cen-
ter show spend $63 on
average when shopping
in the downtown area

(B) restaurants near the
Farmsley Center tend to
be more expensive than
restaurants in outlying
areas

(D) the Farmsley Center
is the only downtown
theatre large enough to
afford to show newly-re-
leased major Hollywood
films

(E) most of the people
who attend films or
performances at the
Farmsley Center do so
because they are already
in the area to shop

CA:S ABCDE
3ya: F built

RS: F ppl spend $96 avg
other stuff

3ya: F built

RS: F ppl spend $96 avg
other stuff

CA:S ABCDE
3ya: F built

RS: F ppl spend $96 avg
other stuff

3ya: F built

RS: F ppl spend $96 avg
other stuff

/ did think of something like this. . . but wait,
this says people who dont attend a show
spend less than those who do. If anything, that
would strengthen the idea that F DOES help
drive the economic revitalization. That's the
opposite of what I want.

Hmm. This would mean that people maybe
spend more money if they re going to a show
at F because the restaurants are more expen-
sive. But I dont even know whether people
are going to restaurants on the day they go to
a show at F. Vd have to make a few assump-
tions here to make this work.
I dont think this has anything to do with
the conclusion at all. The conclusion is about
F overall, not the different kinds of things
people can watch at F. And what does it
matter how F earns its money as long as its
earning money?

Heres a good reason why people might go to F
vs. other places: this is the only place they can
see big Hollywoodfilms. Oh, but this answer
is like answer A — / want something that will
support the idea that F is NOT necessarily a
major driver of Ms revitalization. This one
makes it sound like F IS an important factor.
People go downtown to shop. While they're
there, they think, "oh, hey, lets go see a show."
I see. So people arent coming downtown
specifically because F is there; they re already
downtown and just happen to see F and de-
cide to stay. That would make it more likely
that F isnt necessarily a driving factor in Ms
revitalization.

GMAT

231

Complete the Argument

Common Trap Answers

The common trap answers will mirror the trap answers we see on the regular question type. For
example, if the "Complete the Argument" structure really reflects a Strengthen question, as our last
problem did, then we should expect to see the same trap answers that we see on regular Strengthen
questions: Reverse Logic (weakens rather than strengthens, as in answers A and D above) and No Tie to
the Conclusion (as in answers B and C, above).

Takeaways for Complete the Argument Questions

Several question types can be written using a Complete the Argument structure, though most CA ques-
tions come in the Strengthen or Assumption formats. The CA format will always present an underlined
blank in the argument, and there will not be a question stem following the argument.

Our first task is to figure out what kind of question we really have. The presence of the words "since" or
"because" immediately before the blank indicate a Strengthen / Assumption-type question. On these,
our task will be to find something that supports the argument in some way. Alternatively, if the lan-
guage before the blank says something similar to "it should be expected that," then we are looking at
an Inference-type CA. Finally, we might be asked to "illustrate" or "provide an example of" something
that was discussed in the argument

Trap answer types will follow the normal patterns for questions of that type; for example, a Strengthen
CA will have the usual Strengthen-type traps, and an Inference CA will have the usual Infer-type traps.

Complete the Argument Chapter 7

Problem Set

1. Connecting Flight

Which of the following most logically completes the argument?

John was flying from San Francisco to New York with a connecting flight in Chi-
cago on the same airline. Chicago's airport consists of several small stand-alone
terminals, and it often takes passengers thirty to forty minutes to move between
terminals. John's plane into Chicago arrived on time. The flight attendant assured
John that he would not miss his connecting flight thirty minutes later, because

(A) John's airline is known for always being on time

(B) another passenger on John's first flight was also scheduled to take John's
connecting flight

(D) John knew there was another flight to New York scheduled for one hour
after the connecting flight he was scheduled to take

(E) the airline generally closes the doors of a particular flight ten minutes before
it is scheduled to take off

2. Motor City

Which of the following best completes the passage below?

A nonprofit organization in Motor City has proposed that local college students
be given the option to buy half-price monthly passes for the city's public trans-
portation system. The nonprofit claims that this plan will reduce air pollution in
Motor City while increasing profits for the city's public transportation system.
However, this plan is unlikely to meet its goals, as ,

(A) most college students in Motor City view public transportation as unsafe

(B) most college students in Motor City view public transportation as prohibi-
tively expensive

(C) college students typically do not have the 9-to-5 schedules of most workers,
and can thus be expected to ride public transportation at times when there
are plenty of empty seats

(D) a bus produces more air pollution per mile than does a car

(E) a large proportion of the college students in Motor City live off campus

MANHATTAN
GMAT

Chapter 7

Complete the Argument

3. Deep-brain Stimulation

Which of the following most logically completes the argument given below?

Deep-brain stimulation is a new technique for combating severe depression. In a
recent experiment, electrodes were implanted into the brains of six patients who
had not responded to any currently approved treatment for depression. When an
electrical current to the electrodes was switched on, four of the patients reported
feeling a dramatic reduction in depressive symptoms. The long-term prospects of
the new treatment are not promising, however, because ,

(A) other treatments for depression may also be effective

(B) the other two patients reported only a slight reduction of depressive symp-
toms during the treatment

(D) when the electrical current is interrupted, the effects of the treatment are
reversed

(E) in a subsequent experiment, a one-hour treatment with the electrodes
resulted in a sustained remission from depression in the four patients for six
months

4. Mutual Funds

Which of the following most logically completes the argument?

Many managers of mutual funds proclaim that they have been able to generate
consistently higher rates of return on their investments than the general stock
market by buying shares of undervalued companies. Classical economic theory,
however, proposes the "efficient capital markets hypothesis," which indicates that
stock prices accurately reflect the value of the underlying investments, incor-
porating all information available to the public. If the efficient capital markets
hypothesis is correct, then it should be expected that .

(A) mutual fund managers, in order to compete with each other, will bid up the
prices of certain stocks beyond their true values

(B) mutual fund managers use insider information, an illegal practice, to gener-
ate higher rates of return than the general stock market

(D) based upon public information alone, companies cannot reliably be labeled
undervalued or overvalued relative to the general stock market

(E) some mutual fund managers are better than others at generating a higher
rate of return on investments

MANHATTAN
GMAT

Warn

Complete the Argument

Chapter?

5. Law of Demand

Which of the following best completes the passage below?

The law of demand states that, if all other factors remain equal, the higher the
price of a good, the less people will consume that good. In other words, the
higher the price, the lower the quantity demanded. This principle is illustrated
when ,

(A) Company A has a monopoly over the widget market so an increase in wid-
get prices has little effect on the quantity demanded

(B) a manufacturer of luxury cars noticed that its customer base is relatively
unresponsive to changes in price

(D) an increase in the number of computer retailers led to a decrease in the
average price of computers

(E) a reduction in the price of oranges from $2 per pound to $1 per pound re-
sults in 75 pounds of oranges being sold as opposed to 50 pounds

MANHATTAN
GMAT

Complete the Argument

Chapter 7

Solutions

1. Connecting Flight: The correct answer is C.
Step 1: Identify the question.

Which of the following most CA A B C D E

logically completes the argu-
ment?

Step 2: Deconstruct the argument.

John was flying from San
Francisco to New York with a
connecting flight in Chicago on
the same airline.

Chicago's airport consists of sev-
eral small stand-alone terminals,
and it often takes passengers
thirty to forty minutes to move
between terminals.
Johns plane into Chicago ar-
rived on time.

The question appears before the
argument, and the argument con-
tains a blank at thf end. Both of
these things indicate that this is a
Complete the Argument question.

Straight fact describing his trip.

Okay, it takes a long time to move
between terminals in the Chicago
airport.

And another fact. . .

CA A B C D E
J: SF->C-*NYsame line

CA A B C D E

J: SF->C->NYsame line

C: mult terms, long time to
move term

CA A B C D E

J: SF->C->NYsame line

C: mult terms, long time to
move term

fit on time

CA A B C D E

J: SF->C->NYsame line

C: mult terms, long time to
move term

fit on time

Step 3: State the Goal.

The FA claims that J will make his connecting flight in 30 minutes, so she must be assuming it's not going
to take him more than 30 minutes to get to the gate for his next flight. I need to find an answer choice that
somehow reflects that — something that makes it more likely that J will get to his next gate in less than 30
minutes.

The flight attendant as-
sured John that he would not
miss his connecting flight
thirty minutes later, because

Here we go: the FA claims that J
wont miss his next flight. What's
her evidence for that? That'll be
the right answer.

1 -V

MANHATTAN
GMAT

Chapter 7

Complete the Argument

Step 4: Work from wrong to right.

(A) John's airline is
known for always being

on time

(B) another passenger
on Johns first flight was
also scheduled to take
John's connecting flight

(D) John knew there
was another flight to
New York scheduled
for one hour after the
connecting flight he was
scheduled to take

CA A B C D E

J: SF-»C->NYsame
line

C: mult terms, longtime
to move term

fit on time

J: SF^C^NYsame
line

C: mult terms, long time
to move term

fit on time

J: SF->C-»NYsame
line

C: mult terms, long time
to move term

fit on time

CA ABCDE

J:SF->C-*NYsame
line

C: mult terms, long time
to move term

fit on time

We already know that Js plane to Chicago is
on time, so that doesnt change anything for
this first flight. For the connecting flight, the
only thing that would make the situation bet-
ter is if that flight were late — because then
John would have more time to get there. This
one isnt it.

Does that mean they can somehow get to the
next gate faster because there are two of them?
I dont think so. If they said they were going to
hold the plane because there were two people
coming, that would help. . . but they didnt
say that.

Ah — / isnt going to have to change termi-
nals! We dont know how long it takes to
move around the same terminal, but the
argument does say that it typically takes 30
to 40 minutes to change terminals, so it likely
takes less time when you re staying in the same
terminal. This increases the likelihood that J
will make his connecting flight. This might
be it.

This is only relevant if J misses his flight. . .
but the FA claimed that J would make his
flight.

MANHATTAN
GMAT

Complete the Argument

(E) the airline gener-
ally closes the doors
of a particular flight
ten minutes before it is
scheduled to take off

A BOB E

J: SF-»C->NYsame
line

C: mult terms, long time
to move term

fit on time

This hurts J's chances; now, he only has 20
minutes to make his next flight. Definitely
not.

2. Motor City: The correct answer is A.
Step 1: Identify the question.

Which of the following best
completes the passage below ?

Step 2: Deconstruct the argument.

A nonprofit organization in Mo-
tor City has proposed that local
college students be given the
option to buy half-price month-
ly passes for the city's public
transportation system.
The nonprofit claims that this
plan will reduce air pollution
in Motor City while increas-
ing profits for the city's public
transportation system.
However, this plan is un-
likely to meet its goals, as

CA A B C D E The question appears before the

argument, and the argument con-
tains a blank at the end. Both of
these things indicate that this is a
Complete the Argument question.

CA A B C D E This is a fact — the organization

NPMC: give coll stud 1/2 off has proposed this plan.
pub trans

A B C D E

NP: give coll stud 1/2 off pub
trans -» I air poll, t prof

A B C D E

Step 3: State the Goal.

NP: give coll stud 1/2 off pub
trans 4 air poll, t prof

Okay, the NP claims something,
but Tm not labeling this the
conclusion, because the conclu-
sion is supposed to be in the final
sentence ofCA questions.
This is the conclusion. The author
thinks the plan wont work. Why?

The author believes that the nonprofits plan is not going to work, and I need to find a reason why. The plan
is to let college students buy public transportation passes for half-price in order to reduce air pollution and
increase profits.

Chapter?

Complete the Argument

Step 4: Work from wrong to rig ht.

(A) most college stu-
dents in Motor City
view public transporta-
tion as unsafe

(B) most college stu-
dents in Motor City
view public transporta-
tion as prohibitively
expensive

(C) college students
typically do not have
the 9-to-5 schedules of
most workers, and can
thus be expected to ride
public transportation

at times when there are
plenty of empty seats

(D) a bus produces more
air pollution per mile
than does a car

CA ABCDE

NP: give coll stud 1/2 off
pub trans -> 4 air poll, t
prof

NP: give coll stud 1/2 off
pub trans -» 4 air poll, t
prof

NP: give coll stud 1/2 off
pub trans 4 air poll, t
prof

©BUT wont work

ABCDE

(E) a large proportion
of the college students
in Motor City live off
campus

NP: give coll stud 1/2 off
pub trans -> 4 air poll, t
prof

CA ®B € D E

NP: give coll stud 1/2 off
pub trans -» I air poll, t
prof

If this is the case, then the students wouldn't
want to use public transport at all, even if
they were given a discount. That would make
the plan unlikely to succeed. This might be it!

If they don't use public transport specifically
because it's too expensive, then giving the
students a discount is likely to make them use
public transport more. This makes the plan
more likely to succeed, not less likely.

If this were true, it'd be good news for the
public transport's profits — the students
would be filling what are currently empty
seats.

At first, this sounds good — if a bus produces
more air pollution than a car, then using
more buses would create more air pollution,
which would hurt the plan. But the plan
isn't to use more buses; it's to put more people
on the already-running buses. Plus, a car
typically holds only 1 or 2 people; if 10 people
stop using cars and take 1 bus instead, air
pollution may indeed be decreased.
This makes it likely that the students need
some method of transportation to get to
school — if they're using cars now and switch
to buses, then the plan just might work.

240

GMAT

Complete the Argument

Chapter 7

3. Deep-brain Stimulation: The correct answer is D.
Step 1: Identify the question.

Which of the following most
logically completes the argu-
ment given below?

Step 2: Deconstruct the argument.

Deep-brain stimulation is a new
technique for combating severe
depression.

In a recent experiment, elec-
trodes were implanted into the
brains of six patients who had
not responded to any currently
approved treatment for depres-
sion.

When an electrical current to
\ the electrodes was switched on,
! four of the patients reported
I feeling a dramatic reduction in
depressive symptoms.
The long-term prospects of
the new treatment are not
promising, however, because

CA A B C D E

CA A B C D E
DBS combat depr

CA A B C D E
DBS combat depr
Tested on 6 ppl

CA A B C D E
DBS combat depr
Tested on 6 ppl, 4 better

Step 3: State the Goal.

The question appears before the
argument, and the argument con-
tains a blank at the end. Both of
these things indicate that this is a
Complete the Argument question.

Straight fact.

This tells me how it works and
that they tested it on 6 people.

And four of the people got a lot
better.

Oh, but the author thinks the
treatment's not really going to
work long-term. Why?

The author describes a new medical treatment but says it's probably not going to be good long-term; I need
to find a reason why. So far, the only evidence they've given makes DBS sound promising, so I've got to find
something that shows a flaw or weakness in the treatment.

GMAT

241

Chapter 7

Complete the Argument

Step 4: Work from wrong to right.

(A) other treatments for
depression may also be
effective

(B) the other two
patients reported only
a slight reduction of
depressive symptoms
during the treatment

CA A B C D E

DBS combat depr

Tested on 6 ppl, 4 better

DBS combat depr

Tested on 6 ppl, 4 better

(D) when the electrical

current is interrupted,
the effects of the treat-
ment are reversed

CA A B £ D E

DBS combat depr

Tested on 6 ppl, 4 better

DBS combat depr

Tested on 6 ppl, 4 better

(E) in a subsequent
experiment, a one-
hour treatment with
the electrodes resulted
in a sustained remis-
sion from depression in
the four patients for six
months

This is probably true in the real world, but
talking about other treatments doesn't explain
why DBS won 't be a good treatment long-
term.

When I saw the word "only, " I was expecting
them to say they had a bad result, but actu-
ally having even a slight reduction is better
than nothing, especially for people who have
tried other treatments that haven 't worked.
So, if anything, this is a plus for DBS. That's
not what I want.

I can believe this is true, but we would expect
any major medical treatment to be performed
by skilled physicians, so why would this make
DBS not work long-term?

That's interesting. So, when the current is on,
the symptoms go away, but when the current
is off, the depression comes back. That means
they'd have to be connected to some machine
all the time — they couldn't just get a treat-
ment once a week or once a month. That
definitely makes the treatment less practical
and promising. Unless E is better, this might
be it.

This is almost the opposite ofD. If you get a
one-hour treatment, then the symptoms go
away for 6 months — that's great for DBS!
This can't be the right answer.

MANHATTAN
GMAT

Complete the Argument

4. Mutual Funds: The correct answer is D.

Step 1: Identify the question.

Which of the following most
logically completes the argu-
ment?

Step 2: Deconstruct the argument.

Many managers of mutual
funds proclaim that they have
been able to generate consistent-
ly higher rates of return on their
investments than the general
stock market by buying shares
of undervalued companies.
Classical economic theory,
however, proposes the "efficient
capital markets hypothesis,"
which indicates that stock prices
accurately reflect the value of
the underlying investments,
incorporating all information
available to the public.
If the efficient capital markets
hypothesis is correct, then
it should be expected that

CA A B C D E

MF: buy I val corns -» >
return than SM

CA A B C D E

MF: buy 4 val corns >
return than SM

BUT CET: stock $ is right
based on public info

CA A B C D E

MF: buy 1 val corns -» >
return than SM

BUT CET: stock $ is right
based on public info

The question appears before the
argument, and the argument con-
tains a blank at the end. Both of
these things indicate that this is a
Complete the Argument question.

These managers claim something,
but Vm betting the argument
will disagree. Usually, when the
author says someone else claims
something, then the author dis-
agrees. Lets see.

Okay, the author is disagreeing.
This sentence is a little hard to
understand, but it sounds like its
saying that there arent "under-
valued" companies because the
stock price should generally reflect
the accurate value of the company.

Hmm. Vm not sure how to write
that down. It's just saying that if
my second line is true, then some-
thing else should be true, too.

Step 3: State the Goal.

This is one of the more rare variations of the complete the argument type. Rather than asking me to strength-
en something or find an assumption, they're asking me to find something that follows, or must be true based
on the given info. In other words, this is really an Inference question.

The CET says that stock prices generally accurately reflect the company's actual value. If that s true, then the
MF managers must be wrong.

Chapter 7

Complete the Argument

Step 4: Work from wrong to right.

(A) mutual fund man-
agers, in order to com-
pete with each other,
will bid up the prices of
certain stocks beyond
their true values

(B) mutual fund manag-
ers use insider informa-
tion, an illegal practice,
to generate higher rates
of return than the gen-
eral stock market

(D) based upon public
information alone, com-
panies cannot reliably
be labeled undervalued
or overvalued relative to
the general stock market

(E) some mutual fund
managers are better
than others at generat-
ing a higher rate of
return on investments

CA A B C D E j They're supposed to be buying "undervalued"

stocks, so bidding up the price doesn't make
any sense. This doesnt follow from the argu-
ment.

MF: buy I val corns >
return than SM

BUT CET: stock $ is right
based on public info

CA A B C D E

MF: buy I val corns -> >
return than SM

BUT CET: stock $ is right
based on public info

CA A B € D E

MF: buy I val corns -» >
return than SM

BUT CET: stock $ is right
based on public info
CA A B € D E

MF: buy I val corns >
return than SM

BUT CET: stock $ is right
based on public info

CA AB€@E

MF: buy 4 val corns >
return than SM

BUT CET: stock $ is right
based on public info

I suppose this could be true of some people,
but I don't think this is something that abso-
lutely has to follow from the argument.

This might be true for many stocks, but there
are also companies that go down and even go
out of business.

This one's a little difficult to understand. If
we only know public info, then companies
aren't under- or overvalued. . . so that would
mean they're correctly valued. . . oh, wait,
that's similar to what the theory said. It said
that prices do accurately reflect the value of
the companies. Okay, this might be it.
Again, I can believe this is true in general,
but the argument, doesn't talk about whether
some MF managers are better than others.
Rather, it's talking about this CET thing and
I how it goes against what the MF managers
say.

5. Law of Demand: Correct answer is E.

Step 1: Identify the question.

Which of the following best
completes the passage below?

CA A B C D E The question appears before the

argument and the argument con-
tains a blank at the end. Both of
these things indicate that this is a
Complete the Argument question.

MANHATTAN
GMAT

Complete the Argument

Chapter 7

Step 2: Deconstruct the argument.

The law of demand states that,
if all other factors remain equal,
the higher the price of a good,
the less people will consume
that good.

In other words, the higher the
price, the lower the quantity
demanded.

CA A B C D E

LD: = factors, t $ -» I
consume

A B C D E

This principle is illustrated
when .

LD: = factors, t $ -» I
consume

CA A B C D E

LD: = factors, T $ -» I
consume

They're giving me a "general law, "
which is essentially a fact.

This basically says what I already
wrote y so Fm not going to write
anything else down.

This is another one of those weird
forms. They re not asking me to
give a reason why or to find a
conclusion. They re asking me to
find an example that illustrates
the "general law" they gave above.

Step 3: State the Goal.

This is an interesting one. I need to find an example that illustrates this general principle: when some-
thing costs more, then people don't want to buy it as much. The opposite would be true, too: when
something costs less, then people do buy it more.

Step 4: Work from wrong to right.

(A) Company A has
a monopoly over the
widget market so an
increase in widget prices
has little effect on the
quantity demanded

(B) a manufacturer of
luxury cars noticed
that its customer base is
relatively unresponsive
to changes in price

CA A B C D E

LD: = factors, t $ -> I
consume

A B C D E

LD: = factors, t $ -» I
consume

This says that an increase in price does not
change demand, but the LD said that an
increase in price should lower demand, so this
cant be an example ofLD.

Again, this is saying that a change in price
doesnt really affect demand, which is not
what the LD theory said.

MANHATTAN
GMAT

245

Chapter 7

Complete the Argument

CA AfiGDE

LD: = factors, t $ -» I
consume

(D) an increase in the
number of computer
retailers led to a decrease
in the average price of
computers

CA AfiGDE

LD: = factors, f $ -> I
consume

consume

(E) a reduction in the CA A fi € B(g)

price of oranges from LD: = factors, t $ -> I

$2 per pound to $1 per
pound results in 75
pounds of oranges being
sold as opposed to 50
pounds

Hmm. So maybe an increase in the gaso-
line price is causing people not to want to
use as much gas? They didn't actually say
that directly, though — they just said more
people are taking public transport. Maybe
the population is growing It could be the
case that people are still buying just as much
gasoline even though the price went up. This
one doesn't work.

Increase and decrease — that's good! Oh wait.
Its not an increase in price vs. a decrease in
number sold. Its an increase in number of
stores selling computers to a decrease in price.
That's not quite the same, but it's still closer
than the first three answers. IfE isn't better, I
guess I'll choose this one.
Tricky! Okay, they're giving me the other side
of the rule. If it's true that higher price leads
to lower consumption, then it's also true that
higher consumption means there were lower
prices. And that's what this one says — the
price goes down and people buy more. This
one's better than D!

MANHATTAN
GMAT

Critical Reasoning

Wrong Answer Analysis

On This Chapter. . ,

Out of Scope
Reverse Logic
The Mix Up

Wrong Answer Analysis

In previous chapters, we have examined a number of question types along with their common traps, or
wrong answer types. This chapter is a summary of the "wrong answer" information scattered through-
out the question-types chapters, and it also contains additional examples to illustrate the characteristics
of these common traps.

We've talked about many different types, so we're going to group them into three big categories:

1. Out of Scope

2. Reverse Logic

3. The Mix Up

Out of Scope

Generally speaking, "out of scope" answers miss or go beyond the scope of the argument in some way.
The "scope" refers to what the argument covers. If the author claims that women over five feet ten
inches tall all make good basketball players, then the scope is limited to women (as opposed to men)
with a certain physical characteristic (over five feet ten inches tall) and to the sport of basketball (as
opposed to, say, hockey). If an answer focuses on men (the wrong group) and doesn't mention women at
all, that answer is out of scope.

There are several different ways in which the test writers will try to take an answer out of the scope of
the argument. On Assumption Family and Evaluate a Discrepancy questions, it's quite common to find
answers that talk about the wrong detail (group, activity, action, characteristic, or other detail). For our
mini-argument in the last paragraph, men would be the wrong group, hockey would be a wrong activ-
ity, less than five feet ten inches tall would be a wrong characteristic, and so on. The answer may sound
as though it is related to the argument, but the details will take that answer out of scope.

249

Wrong Answer Analysis

A variation on the last trap is the no tie to the conclusion trap, which we see on Strengthen and Weak-
en questions, and the no tie to the discrepancy trap, which we see on Discrepancy questions. In all of
these cases, we are asked to do something to the conclusion or discrepancy, and in all of these cases, the
trap answer does not affect the conclusion or discrepancy at all.

Take a look at this example:

Question

"No Tie to the Conclusion" Wrong Answer

Which of the following, if true, best supports
the claim that women who are under five feet
ten inches tall cannot have successful careers
as basketball players?

Women who are over five feet ten inches tall
are more likely to excel at basketball.

In many ways, the wrong answer seems relevant: it's talking about women and basketball; it mentions
the "five feet ten inch" height threshold. It does not, however, provide any information about women
who are under five feet ten inches tall. The conclusion claimed something about this specific group of
women. If the answer on a Strengthen the Conclusion question does not actually address the given
conclusion, then it is out of scope. The same is true for Weaken questions.

Discrepancy questions provide us with some sort of discrepancy, and it is also possible for a wrong an-
swer not to address the discrepancy. This is the same type of trap answer as a "no tie to the conclusion."
For instance, an argument might tell us:

Amy loves basketball, yet she's not attending tonight's game even though she has
tickets.

It sounds like Amy would normally go to the game. Why isn't she? That's the discrepancy. A "no tie"
wrong answer might say something like:

Amy's friends also love basketball and plan to go to the game.

Why is this wrong answer not tied to our discrepancy at all? The argument mentions only Amy — what
Amy thinks and what Amy plans to do. The answer choice talks about the wrong group — Amy's
friends, rather than Amy. Unless the argument told us that Amy was influenced by her friends in some
way (thereby making her friends part of the argument), we don't care what her friends think or do.
That's out of the scope of the argument.

We also often see wrong answer choices that make an irrelevant distinction or comparison; these
tend to appear primarily on Assumption Family questions. For instance, consider this argument:

Students who earn A and B grades are more likely to participate in sports than are
students who earn C grades. Therefore, participation in sports helps students to
achieve higher grades.

Wrong Answer Analysis

Chapter 8

Lets say that we re asked to find an assumption. An incorrect answer might say something like:

Students who earn A grades participate in sports even more frequently than do
those who earn B grades.

The argument grouped together the A and B students and treated them in the same way. The answer
separates, or makes a distinction between, the A and B students. On Find the Assumption questions,
our task is to find something that the author must believe to be true in order to draw his conclusion.
Is it absolutely necessary to believe that the A-students participate in sports even more frequently than
the B -students in order to believe the conclusion that sports participation in general helps students to
achieve higher grades?

No, it's not absolutely necessary to believe that. If it were true, then that would help to strengthen the
conclusion — but we weren't asked to strengthen the conclusion! The distinction between A and B
students is irrelevant, since the argument puts them in the same category. In other words, the argument
itself makes absolutely no distinction between A and B students, so why would it be necessary to make
a distinction in order to accept the conclusion?

This example also illustrates another type of trap answer: the real world distraction. This type of
answer sounds reasonable to assume in everyday, real-world conversations, but the information does
not actually fulfill whatever we're supposed to be doing for that question type. For instance, on Find
the Assumption (FA) questions, as we just discussed, we're trying to find something that must be true.
It could be true that A students participate even more then B students, and we might even reasonably
speculate that it is true in the real world, but it doesn't absolutely have to be true in order to draw the
conclusion. We have to hold ourselves to the "must be true" standard on an FA question, so a "real-
world" could-be-true answer is incorrect (though often very tempting!).

In sum, "out of scope" answers can take multiple forms.

Name

Why it's tempting

Why it's wrong

Most likely found in

Wrong detail

May use the same or
similar words from the
argument

It's not the right group,
activity, action, charac-
teristic, or other detail.

Find Assumption,
Evaluate, Strengthen,
Weaken, Inference,
Discrepancy

No tie to the
conclusion (or
discrepancy)

Likely to use the same or
similar words from the
argument

The question asks us
to address the conclu-
sion or discrepancy;
this answer does not
affect the conclusion or
discrepancy.

Strengthen, Weaken,
Discrepancy

MANHATTAN
GMAT

Chapter 8

Wrong Answer Analysis

Irrelevant
distinction or
comparison

Does use specific groups,
actions, or other details
from the argument

Tries to separate two
things that the argu-
ment places into the
same category.

Find Assumption,
Evaluate, Strengthen,
Weaken

Real world
distraction

Is the kind of thing that
people might conclude
or assume in the real
world; could actually be
true in the real world

1 he question asks us
to find something that
must be true and this
answer doesn't have to
be true.

Inference

Reverse Logic

One of the easier traps to fall into is the "reverse logic" trap, when we accidentally pick the opposite of
what we really want, such as an answer that strengthens on a Weaken question. Reverse logic traps oc-
cur most frequently on Assumption Family and Structure Family questions.

One of the most common ways in which we fall into this trap is to misidentify the conclusion, particu-
larly when the argument contains two "sides," or points of view. Consider this example.

Some companies tie bonuses to company performance as well as personal perfor-
mance, on the theory that individual performance is only valuable as far as it ben-
efits the company as a whole in some way. This is counter-productive, however,
because the highest-performing employees are essentially penalized by receiving
a bonus commensurate only with the average performance of the overall compa-
ny, thereby leading to a lack of motivation to continue to outperform their peers.

What are the claims here? Some companies think that "individual performance is only valuable if it
benefits the company as a whole" and set up their bonus plans accordingly. Some unknown person, on
the other hand, thinks that this viewpoint is "counter-productive" and will "[lead] to a lack of motiva-
tion" on the part of the best employees. Which is the main conclusion?

The authors point of view is always the main conclusion. In this case, the "unknown person" is the
author. If a claim is attributed to a particular person or group, that claim is likely not the authors claim.
A claim that is simply asserted, with no commentary as to who is doing the asserting, is likely to be the
author s claim.

We can see how easy it would be to mix up the claims, though, and that in turn would make it easy to
pick a "Reverse Logic" answer, since the two claims are on opposing sides of the fence.

MANHATTAN
GMAT

Wrong Answer Analysis

Chapter 8

Lets say that we have this question:

Some companies tie bonuses to company performance as well as personal per-
formance, on the theory that individual performance is only valuable as far
as it benefits the company as a whole in some way. This is counter-productive,
however, because the highest-performing employees are essentially penalized
by receiving a bonus commensurate only with the average performance of the
overall company, thereby leading to a lack of motivation to continue to outper-
form their peers.

In the argument given, the portion in boldface plays which of the following roles?

And here are our two answer choices:

(A) It is the main conclusion of the argument

(B) It is a judgment that the argument opposes.

If we identify the boldface statement as the conclusion (of "some companies"), then we'd pick answer A.
But if we identify the "lack of motivation" comment as the true conclusion, then the boldface statement
goes against the conclusion and the answer is clearly B.

Alternatively, what if we were asked this question for the same argument?

Question

Reverse Logic trap answer

Correct Answer

Which of the following, if true,
would most seriously under-
mine the argument above?

The performance of employees
who feel they aren't appropri-
ately compensated for their
efforts often drops.

High-performing employees
typically state that their pri-
mary motivation is the satisfac-
tion of a job well done.

Strengthens

Weakens

In this example, the Reverse Logic trap strengthens the conclusion instead of weakening it (and it is
even easier to fall into this trap if you misidentify the conclusion!). The trap answer, above, reinforces
(or strengthens) the authors conclusion: people whose pay is below their performance may lose motiva-
tion to work hard. The correct answer, on the other hand, does weaken the author s conclusion by offer-
ing a reason why employees might continue to work hard regardless of compensation levels.

In general, make sure to check the logical "direction" of the answers; if something fits one of the follow-
ing categories, its a trap!

MANHATTAN
GMAT

Chapter 8

Wrong Answer Analysis

Question Type

Reverse Trap answer will

Role

assign the opposite role of the correct
role

Find Assumption

actually hurt the argument if it is true

Strengthen

weaken the conclusion

Weaken

strengthen the conclusion

The Mix Up

Our final major wrong answer category is "The Mix Up." These can appear in a few different varieties.

The one word off variety is simple, in the sense that only a single word can make the answer wrong,
but also quite difficult and tempting. . . because only a single word makes the difference! (Note: it could
also be two or three words.) These wrong answers most often show up in Describe the Role, Describe
the Argument, and Inference questions.

For example, what's the difference between the below two answer choices?

The first is a prediction that supports a position that the argument concludes.

The first is a prediction that supports a position that the argument opposes.

Only one word is different — the very last word — and yet that one word changes everything. The first
sample answer is describing a premise: something that supports the author's conclusion. The second,
on the other hand, is describing a counter-premise: something that goes against the author's conclusion.
If were reading too quickly or skim over a word, that can be the difference between picking the right
answer and falling for a tempting trap.

We also have to be on the alert for the switching terms trap, which occurs most often on Inference and
Find the Assumption questions. The answer choice will use actual wording or terminology from the
argument, but it will switch terms around or pair things that weren't actually paired in the argument.
For instance, what if we were asked to infer something about the following argument excerpt?

Argument excerpt

Switching Terms Trap Answer

Studies have shown that holding a blood drive
tends to stimulate the participation of members
of an organization and increase the number of
donations.

(B) Holding a blood drive helps an organization
to increase the number of members.

MANHATTAN
GMAT

Wrong Answer Analysis

Chapter 8

See what answer choice B did there? Its certainly possible that answer choice B is true, but it doesn't
accurately reflect what the argument actually said. Answer B contains many of the same words found in
the argument, but in a mixed-up way. The argument said that the number of donations would increase,
not the number of members. On an inference question, that is sufficient to eliminate this answer, be-
cause on inference questions, we are looking for an answer that must be true.

255

GMAT

Wrong Answer Analysis Chapter 8

Problem Set

The problem set consists of problems that you have already seen in earlier chapters of this book. Note:
if you have not yet done these problems, then do them normally under the 2-minute time constraint for
the first time before doing the exercise described below.

For each of the following problems, identify the right answer, and try to articulate why each wrong
answer is wrong. If you spot a particular category of wrong answer, write that down as well, but remem-
ber that the real test won't ask us to classify. Rather, our goal is to train ourselves to be able to identify
wrong answers accurately and efficiently; the wrong answer categories are just a tool to help us practice
this. Also note that some wrong answers may not fit into any of the common categories listed in this
chapter.

1. Gray Wolf Population

From Chapter 3, Structure Family

The environmentalist challenges the government representative's argument by
doing which of the following?

introducing additional evidence that undermines an assumption made by
the representative

challenging the representative's definition of a critical breeding number
demonstrating that the critical breeding number of the two wolf popula-
tions differs significantly

implying that the two populations of wolves could be combined in order to
preserve the species

suggesting that the Montana wolf population grew at a faster rate than
stated in the representative's argument

MANHATTAN
GMAT

Chapter 8

Wrong Answer Analysis

2. Malaria

From Chapter 3, Structure Family

What function does the statement in boldface fulfill with respect to the argument
presented above?

(A) It provides support for the explanation of a particular phenomenon.

(B) It presents evidence that contradicts an established fact.

(D) It identifies the cause of an erroneous conclusion.

(E) It proposes a new conclusion in place of an earlier conjecture.

3. Oil and Ethanol

From Chapter 4, Assumption Family

Which of the following must be assumed in order to conclude that Country N will
succeed in its plan to reduce its dependence on foreign oil?

(A) Electric power is not a superior alternative to ethanol in supplementing
automobile gasoline consumption.

(B) In Country N, domestic production of ethanol is increasing more quickly
than domestic oil production.

(D) In Country N, gasoline consumption is not increasing at a substantially
higher rate than domestic oil and ethanol production.

(E) Ethanol is as efficient as gasoline in terms of mileage per gallon when used
as fuel for automobiles.

MANHATTAN
GMAT

Wrong Answer Analysis

Chapter 8

4. Charity

From Chapter 4, Assumption Family

Which of the following best explains why the consultants' reasoning is flawed?

(A) Marketing efforts are only one way to solicit charitable donations.

(B) Not all impoverished families donate to charity.

(C) Some charitable marketing efforts are so expensive that the resulting dona-
tions fail to cover the costs of the marketing campaign.

(D) Percentage of income is not necessarily indicative of absolute dollar value.

(E) People are more likely to donate to the same causes to which their friends
donate.

5. Food Allergies

From Chapter 4, Assumption Family

Food allergies account for more than thirty thousand emergency department
visits each year. Often, victims of these episodes are completely unaware of their
allergies until they experience a major reaction. Studies show that 90 percent of
food allergy reactions are caused by only eight distinct foods. For this reason, in-
dividuals should sample a minuscule portion of each of these foods to determine
whether a particular food allergy is present.

Which of the following must be studied in order to evaluate the recommendation
made in the argument?

(A) The percentage of allergy victims who were not aware of the allergy before a
major episode

(B) The percentage of the population that is at risk for allergic reactions

(D) Whether an allergy to one type of food makes someone more likely to be
allergic to other types of food

(E) Whether ingesting a very small amount of an allergen is sufficient to pro-
voke an allergic reaction in a susceptible individual

MANHATTAN
GMAT

Chapter 8

Wrong Answer Analysis

6. Smithtown Theatre

From Chapter 5, Assumption Family

Which of the following, if true, would most seriously weaken the argument?

(A) A large movie chain plans to open a new multiplex location in Smithtown
later this year.

(B) Concession sales in the Smithtown Theatre comprise a substantial propor-
tion of the theatre's revenues.

(C) Many recent arrivals to Smithtown are students that are less likely to attend
the Smithtown Theatre than are older residents.

(D) The expansion would allow the Smithtown Theatre to stage larger, more
popular shows that will attract customers from neighboring towns.

(E) The Board of the Smithtown Theatre often solicits input from residents of
the town when choosing which shows to stage.

7. Digital Coupons

From Chapter 5, Assumption Family

The redemption rate for e-mailed coupons is far lower than that for traditionally
distributed paper coupons. One factor is the "digital divide" — those who might
benefit the most from using coupons, such as homemakers, the elderly, and those
in low-income households, often do not have the knowledge or equipment nec-
essary to go online and receive coupons.

Which of the following, if true, does the most to support the claim that the digital
divide is responsible for lower electronic coupon redemption rates?

(A) Computers are available for free in libraries, schools, and community centers.

(B) The redemption rate of ordinary coupons is particularly high among elderly
and low income people that do not know how to use computers.

(D) More homemakers than elderly people would use computers if they had ac-
cess to them.

(E) The redemption rate for coupons found on the internet has risen in the last
five years.

MANHATTAN
GMAT

Wrong Answer Analysis

Chapter 8

8. World Bank

From Chapter 5, Evidence Family

Which of the following can be logically concluded from the passage above?

(A) World Bank voting shares are allocated based upon each country's share of
the world's GDP.

(B) The new ratio of voting share to percentage of world GDP is lower for China
than it is for France.

(D) China should be upset that its voting share does not match its proportion of
the world's GDP.

(E) France lost some of its voting share to China because China comprised a
larger portion of the world's GDP.

9. Bar Codes

Which of the following, if true, most helps to resolve the apparent paradox?

(A) Many smaller stores do not use bar codes at all because of the expense.

(B) For some products, the amount of data necessary to be coded is small
enough to fit fully on a one-dimensional bar code.

(D) Two-dimensional bar codes can also be scanned by consumer devices, such
as cell phones.

(E) One-dimensional bar codes last longer and are less prone to error than two-
dimensional bar codes.

MANHATTAN
GMAT

Wrong Answer Analysis
Solutions

1. Gray Wolf Population

(A) introducing additional evidence that undermines an assumption made by the representative

This is the correct answer.

(B) challenging the representatives definition of a critical breeding number

This is a Mix-Up answer. The environmentalist discusses critical breeding number, not the
representative.

This doesntfit into one of the standard trap categories. The environmentalist does mention
the term "critical breeding number' but does not say that this number differs significantly.
Rather, the environmentalist says that the population size differs.

(D) implying that the two populations of wolves could be combined in order to preserve the species

This is a Real World Distraction answer. It might be an interesting strategy in the real
world, but the argument doesn't mention it.

(E) suggesting that the Montana wolf population grew at a faster rate than stated in the representative's
argument

This is a Mix-Up answer. The environmentalist does mention a number, but that number
does not represent a rate of growth.

2. Malaria

(A) It provides support for the explanation of a particular phenomenon.

This is the correct answer.

(B) It presents evidence which contradicts an established fact.

This doesnt fit into one of the standard trap categories. The boldface text does contradict
what people once thought about malaria, but what they once thought was not an established
fact.

This is a "one word off" trap — nothing was contested in the argument.

Chapter 8

Wrong Answer Analysis

(D) It identifies the cause of an erroneous conclusion.

This could be a Reverse Logic trap; were looking for something that supports the conclusion.

(E) It proposes a new conclusion in place of an earlier conjecture.

This is a general Mix-Up answer; the argument does do this in general, but not the state-
ment in boldface.

3. Oil and Ethanol

(A) Electric power is not a superior alternative to ethanol in supplementing automobile gasoline con-
sumption.

This Out Of Scope answer is the Wrong Detail. The argument is about oil and ethanol, not
electric power.

(B) In Country N, domestic production of ethanol is increasing more quickly than domestic oil produc-
tion.

This doesn't fit into one of the standard trap categories. It sounds pretty good at first glance,
but isn't actually necessary (which is a requirement for a correct answer on an assumption
question).

This seems somewhat Out Of Scope. What does the heating of homes have to do with the
argument?

(D) In Country N, gasoline consumption is not increasing at a substantially higher rate than domestic
oil and ethanol production.

This is the correct answer.

(E) Ethanol is as efficient as gasoline in terms of mileage per gallon when used as fuel for automobiles.

This Out of Scope answer is too specific on the detail, so we can call this a Wrong Detail.
Knowing how efficient the two are generally might help, but they don't necessarily have to
be equally efficient.

4. Charity

(A) Marketing efforts are only one way to solicit charitable donations.

MANHATTAN
GMAT

Wrong Answer Analysis

Chapter 8

This Out Of Scope answer discusses an Irrelevant Distinction. It may be true that there are
other ways to solicit donations besides marketing efforts, but the argument itself is about
marketing efforts.

(B) Not all impoverished families donate to charity.

This answer is One Word Off. It makes a statement about "air impoverished families, but
the argument never says that all of these families act in the same way. (Note: many people
will eliminate this answer because the word "air is extreme. Its true that this argument
does not provide support for the extreme word "all," but extreme words can appear in cor-
rect CR answers — if the argument provides support for the extreme word.)

(C) Some charitable marketing efforts are so expensive that the resulting donations fail to cover the
costs of the marketing campaign.

This is an especially tricky Wrong Detail answer. The argument never talks about whether
the marketing campaign will be "profitable" (that is, make more money than was spent on
the marketing campaign). It might seem like this should be the goal of any charitable mar-
keting campaign. . . but the argument doesn't address this.

(D) Percentage of income is not necessarily indicative of absolute dollar value.

This is the correct answer.

(E) People are more likely to donate to the same causes to which their friends donate.

This sounds plausible in the Real World, but its just a distraction here — the argument
doesnt address this issue.

5. Food Allergies

(A) The percentage of allergy victims who were not aware of the allergy before a major episode

This answer makes an Irrelevant Distinction. Knowing the exact percentage doesnt actually
tell us anything.

(B) The percentage of the population that is at risk for allergic reactions

This answer is Out Of Scope because it talks about all allergies in general, not just food

allergies.

This doesnt fit into one of the standard trap categories. The argument does not hinge on
how commonly used the foods must be in order to warrant testing. Further, the argument
does not limit itself to foods that must be cooked.

MAN

265

GMAT

Chapter 8

Wrong Answer Analysis

(D) Whether an allergy to one type of food makes someone more likely to be allergic to other types of
food

This answer makes an Irrelevant Distinction; the argument doesn't address whether some-
one is allergic to multiple types of food.

(E) Whether ingesting a very small amount of an allergen is sufficient to provoke an allergic reaction in
a susceptible individual

This is the correct answer.

6. Smithtown Theatre

(A) A large movie chain plans to open a new multiplex location in Smithtown later this year.

This one can be considered either Out of Scope (a different movie chain doesnt matter to
this conclusion) or Reverse Logic (if anything, the new movie theatre might take some busi-
ness from Smithtown Theatre, strengthening the authors claim).

(B) Concession sales in the Smithtown Theatre comprise a substantial proportion of the theatres rev-
enues.

This one is Out of Scope because it has No Tie to the Conclusion. Knowing this information
about concession sales tells us nothing new about the Theatres plans to expand.

(C) Many recent arrivals to Smithtown are students that are less likely to attend the Smithtown Theatre
than are older residents.

This is a Reverse Logic trap because it strengthens the authors claim (and this is a weaken
question).

(D) The expansion would allow the Smithtown Theatre to stage larger, more popular shows that will
attract customers from neighboring towns.

This is the correct answer.

(E) The Board of the Smithtown Theatre often solicits input from residents of the town when choosing
which shows to stage.

This sounds good in the Real World, but it really has No Tie to the Conclusion. Two traps
for the price of one!

7. Digital Coupons

(A) Computers are available for free in libraries, schools, and community centers.

MANHATTAN
GMAT

Wrong Answer Analysis

If anything, this answer choice weakens the authors claim, and this is a strengthen ques-
tion. This is a Reverse Logic trap.

(B) The redemption rate of ordinary coupons is particularly high among elderly and low income people
that do not know how to use computers.

This is the correct answer.

This argument focuses on the Wrong Detail. The argument says nothing about having to
have high-speed internet connections.

(D) More homemakers than elderly people would use computers if they had access to them.

This answer is making an Irrelevant Distinction between two groups that are treated the
same in the argument.

(E) The redemption rate for coupons found on the internet has risen in the last five years.

This answer focuses on the Wrong Detail. The argument claims that paper coupons are in
wider use because some people have difficulty accessing electronic coupons.

8. World Bank

(A) World Bank voting shares are allocated based upon each country's share of the worlds GDP.

This sounds as though it could be reasonable in the Real World, but they didnt provide
enough data points to say that this is definitely true.

(B) The new ratio of voting share to percentage of world GDP is lower for China than it is for France.

This is the correct answer.

We can think of this as an Irrelevant Comparison because it says that something is the "most
important factor 7 when the argument doesnt actually say that at all.

(D) China should be upset that its voting share does not match its proportion of the worlds GDP.

This might be reasonable to believe in the Real World, but the argument mentions nothing
about how China "should" feel about anything.

Chapter 8

Wrong Answer Analysis

(E) France lost some of its voting share to China because China comprised a larger portion of the
world s GDP.

We can consider this a Mix-Up answer because it includes many words and terms from the
argument. . . but this answer imposes a cause-effect relationship that wasnt given in the
argument.

9. Bar Codes

(A) Many smaller stores do not use bar codes at all because of the expense.

This choice makes an Irrelevant Distinction. The argument talks about stores that do use
bar codes, not stores that dont.

(B) For some products, the amount of data necessary to be coded is small enough to fit fully on a one-
dimensional bar code.

This one is very tempting, but its also a One Word Off trap. The choice addresses only
"some" products — not enough to affect the conclusion.

This is a Reverse Logic trap. If this choice were true, it would make the discrepancy even
more strange, because it offers another reason why people would want to use 2D bar codes.

(D) Two-dimensional bar codes can also be scanned by consumer devices, such as cell phones.

This can be considered a Reverse Logic trap (because it makes 2D bar codes more attractive)
or a No Tie to the conclusion trap (because scanning with consumer devices isnt part of the
scope of the argument).

(E) One-dimensional bar codes last longer and are less prone to error than two-dimensional bar codes.

This is the correct answer.

268

GMAT

Append ix/A

Critical Reasoning

Official Guide Problem Sets

On This Charter. . ,

Official Guide Problem Sets

Official Guide Problem Sets
Official Guide Problem Sets

Appendix A

Now that you have completed Critical Reasoning, it is time to test your skills on problems that have
actually appeared on real GMAT exams over the past several years.

The problem set that follows is composed of questions from two books published by the Graduate
Management Admission Council® (the organization that develops the official GMAT exam):

The Official Guide for GMAT Review, 13th Edition (pages 33-39 & 500-538)
The Official Guide for GMAT Verbal Review, 2nd Edition (pages 116-152).

These books contain Verbal questions that have appeared on past official GMAT exams. (The ques-
tions contained therein are the property of The Graduate Management Admission Council, which is
not affiliated in any way with Manhattan GMAT.)

Although the questions in The Official Guides have been "retired" (they will not appear on future of-
ficial GMAT exams), they are great practice questions.

Solve each of the following problems in a notebook, making sure to demonstrate how you arrived at
each answer by showing all of your work. If you get stuck on a problem, look back at the Critical Rea-
soning strategies and content contained in this guide to assist you.

Note: Problem numbers preceded by "D" refer to questions in the Diagnostic Test chapter of
The Official Guide for GMAT Review, 13th Edition (pages 33-39).

Describe the Argument:

13th Edition: 34, 84, 85, 123
Verbal Review: 79

Describe the Role:

13th Edition: 18, 28, 63, 76, 78, 89, 98, 116
Verbal Review: 48, 74

Find the Assumption:

13th Edition: 21, 41, 46, 48, 75, 77, 83, 93, 96, 106, 109, 113, D28
Verbal Review: 7, 34, 44, 52, 56, 63, 67, 76

Evaluate the Argument:

13th Edition: 7, 10, 15, 27, 36, 42, 47, 53, 68, 70, 72, 110, 114, 124, D21, D22, D29
Verbal Review: 3, 28, 40, 42, 54, 66, 70

MANHATTAN
GMAT

Appendix A

Official Guide Problem Sets

Flaw:

13th Edition: 8, 100

Strengthen the Argument:

13th Edition: 1, 5, 11, 14, 16, 19, 23, 29, 30, 31, 35, 40, 45, 50, 52, 56, 64, 67, 95, 101,

102, 108, 111, 118, 120, 121, D25, D27, D32
Verbal Review: 1, 2, 6, 9, 13, 17, 21, 23, 25, 29, 30, 32, 33, 35, 37, 45, 51, 55, 58, 62,
65, 68, 69, 77, 78, 82

Weaken the Argument:

13th Edition: 2, 4, 20, 25, 32, 37, 43, 51, 58, 62, 71, 73, 79, 80, 82, 87, 88, 90, 97, 107,

112, 115, 117, 119, 122, D18, D20, D23, D26, D30, D34
Verbal Review: 4, 5, 11, 15, 16, 18, 20, 22, 24, 26, 27, 31, 36, 39, 41, 46, 47, 49, 50, 71,
80, 81, 83

Explain the Discrepancy:

13th Edition: 3, 6, 9, 13, 17, 22, 24, 44, 49, 57, 61, 86, 92, 94, 99, D19, D33
Verbal Review: 8, 59, 60, 61, 72, 73

Inference:

13th Edition: 26, 38, 54, 55, 60, 66, 91, 103, 104, 105, D24, D31
Verbal Review: 12, 14, 19, 43, 53, 57, 64, 75

Complete the Argument:

13th Edition: 12, 33, 39, 59, 65, 69, 74, 81
Verbal Review: 10, 38

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9. CEO: Over the past several years, we have more
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interest charged on outstanding balances from an
annual percentage rate (APR) of 9.5% to an APR of
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Which of the following statements, if true, would most
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order to spur profitable growth?

(A) Many other companies have experienced a similar
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(B) The company's operating expenses are above the
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(C) The increase in default rates was due to a rise in
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